Citation Nr: 1313387 Decision Date: 04/22/13 Archive Date: 05/03/13 DOCKET NO. 05-11 825 ) DATE ) ) On appeal from the Department of Veterans Affairs Regional Office in Lincoln, Nebraska THE ISSUES 1. Entitlement to service connection for diabetes mellitus, type II, to include as due to exposure to an herbicidal agent. 2. Entitlement to service connection for a heart disorder, to include as due to exposure to asbestos and/or an herbicidal agent, to also include as secondary to diabetes mellitus, type II. 3. Entitlement to service connection for bilateral lower extremity neuropathy, to include as due to exposure to an herbicidal agent. REPRESENTATION Veteran represented by: The American Legion ATTORNEY FOR THE BOARD S. Pflugner, Counsel INTRODUCTION The Veteran served on active duty from July 1964 to September 1967 These matters come before the Board of Veterans' Appeals (Board) on appeal from a May 2004 rating decision issued by the Department of Veterans Affairs (VA) Regional Office located in St. Louis, Missouri on behalf of the Regional Office located in Lincoln, Nebraska (RO). FINDINGS OF FACT 1. The Veteran did not serve within the land borders or on the inland waterways of the Republic of Vietnam during his active duty service. 2. Diabetes mellitus, type II, was not shown to have been present during the Veteran's active duty service, or for many years thereafter, nor is it the result of any incident occurring during his active duty service, including as due to exposure to herbicidal agents. 3. The evidence did not show that the Veteran's military occupational specialty exposed him to asbestos, that the Veteran breathed in asbestos, or that a heart disorder was related to inservice asbestos exposure. 4. A current heart disorder was not shown to have been present during the Veteran's active duty service, or for many years thereafter, nor is it the result of any incident occurring during his active duty service, including as due to exposure to herbicidal agents, nor caused or aggravated by a service-connected disability. 5. Bilateral lower extremity peripheral neuropathy was not shown to have been present during the Veteran's active duty service, or for many years thereafter, nor is it the result of any incident occurring during his active duty service, including as due to exposure to herbicidal agents. CONCLUSIONS OF LAW 1. Diabetes mellitus, type II, was not incurred in or aggravated by active military service, nor may it be presumed to have been so incurred or aggravated, to include as due to inservice exposure to an herbicidal agent. 38 U.S.C.A. §§ 1101, 1110, 1112, 1116, 1131, 5103A, 5107 (West 2002 & Supp. 2012); 38 C.F.R. §§ 3.303, 3.307, 3.309 (2012). 2. A heart disorder was not incurred in or aggravated by active military service, nor may it be presumed to have been so incurred or aggravated, to include as due to exposure to asbestos or an herbicidal agent, and is not proximately due to or aggravated by a service-connected disability. 38 U.S.C.A. §§ 1101, 1110, 1112, 1116, 1131, 5103A, 5107 (West 2002 & Supp. 2012); 38 C.F.R. §§ 3.303, 3.307, 3.309, 3.310 (2012). 3. Bilateral lower extremity peripheral neuropathy was not incurred in or aggravated by active military service, to include as due to inservice exposure to an herbicidal agent. 38 U.S.C.A. §§ 1101, 1110, 1112, 1116, 1131, 5103A, 5107 (West 2002 & Supp. 2012); 38 C.F.R. §§ 3.303, 3.307, 3.309 (2012). REASONS AND BASES FOR FINDINGS AND CONCLUSIONS VA has a duty to notify and assist veterans in substantiating claims for VA benefits. 38 U.S.C.A. §§ 5100, 5102, 5103, 5103A, 5107, 5126 (West 2002 & Supp. 2012); 38 C.F.R. §§ 3.102, 3.156 (a), 3.159, 3.326(a) (2012). Proper notice from VA must inform a veteran of any information and medical or lay evidence not of record (1) that is necessary to substantiate the claim; (2) that VA will seek to provide; and (3) that the veteran is expected to provide. Quartuccio v. Principi, 16 Vet. App. 183 (2002). This notice must be provided prior to an initial unfavorable decision on a claim by the RO. Mayfield v. Nicholson, 444 F.3d 1328 (Fed. Cir. 2006); Pelegrini v. Principi, 18 Vet. App. 112 (2004). The notice requirements apply to all five elements of a service-connection claim, including: (1) veteran status; (2) existence of a disability; (3) a connection between the veteran's service and the disability; (4) degree of disability; and (5) effective date of the disability. Dingess/Hartman v. Nicholson, 19 Vet. App. 473 (2006). Further, this notice must include information that a disability rating and an effective date for the award of benefits will be assigned if service connection is awarded. Id. at 486. Prior to the final adjudication of the Veteran's claims, the RO's October 2005 and March 2006 letters advised the Veteran of the foregoing elements of the notice requirements. 38 U.S.C.A. § 5103 (a); 38 C.F.R. § 3.159(b)(1); see Quartuccio v. Principi, 16 Vet. App. 183, 187 (2002); Dingess/Hartman, 19 Vet. App. at 486. After issuing the March 2006 letter, the Veteran's claims were re-adjudicated in May 2010, June 2012, and January 2013 supplemental statements of the case. Prickett v. Nicholson, 20 Vet. App. 370, 376 (2006) (noting that a notice defect may be cured by issuance of a fully compliant notification followed by a re-adjudication of the claim); see also Bernard v. Brown, 4 Vet. App. 384, 394 (1993). Further, the purpose behind the notice requirements has been satisfied because the Veteran has been afforded a meaningful opportunity to participate effectively in the processing of these claims, including the opportunity to present pertinent evidence. Thus, the Board finds that the content requirements of the notice VA is to provide have been met. See Pelegrini, 18 Vet. App. at 120. The duty to assist the Veteran has also been satisfied with respect to each of these service connection claims. The RO has obtained the Veteran's service treatment records and his private and VA treatment records. 38 U.S.C.A. § 5103A; 38 C.F.R. § 3.159. Further, there is no indication in the record that additional evidence relevant to the issues being decided herein is available and not part of the record. See Pelegrini, 18 Vet. App. at 120. In September 2011, the Veteran underwent a VA examination. Supplemental opinions were obtained in October 2011 and November 2012. As a whole, the opinions obtained addressed whether the Veteran's diabetes mellitus, type II, was incurred in or due to his military service. See McLendon v. Nicholson, 20 Vet. App. 79, 83 (2006). The examiners rendered opinions after a thorough review of the Veteran's claims file and a thorough clinical evaluation. As such, the Board finds that September 2011 VA examination, with supplemental opinions, is adequate for purposes of determining the Veteran's entitlement to service connection. See Barr v. Nicholson, 21 Vet. App. 303, 311 (2007). In February 2010, the Veteran underwent a VA examination to ascertain the presence of a heart disorder and bilateral lower extremity peripheral neuropathy. The examiner reviewed the Veteran's claims file, the Veteran's statements, and administered a thorough clinical evaluation. The examiner then render an adequate opinion with respect to the Veteran's heart disorder and determined that the Veteran's bilateral lower extremity peripheral neuropathy was etiologically associated with his diabetes mellitus, type II. Based on the above, the Board finds that the February 2010 VA examination is adequate for determining the Veteran's entitlement to service connection for a heart disorder and bilateral lower extremity peripheral neuropathy. Id. As there is no indication that any failure on the part of VA to provide additional notice or assistance reasonably affects the outcome of this case, the Board finds that any such failure is harmless. See Mayfield v. Nicholson, 20 Vet. App. 537 (2006); see also Dingess/Hartman v. Nicholson, 19 Vet. App. 473 (2006); see also Shinseki v. Sanders, 129 S. Ct. 1696 (2009) (reversing prior case law imposing a presumption of prejudice on any notice deficiency, and clarifying that the burden of showing that an error is harmful, or prejudicial, normally falls upon the party attacking the agency's determination); (2009); Fenstermacher v. Phila. Nat'l Bank, 493 F.2d 333, 337 (3d Cir. 1974) ("[N]o error can be predicated on insufficiency of notice since its purpose had been served."). Historically, the Veteran served on active duty from July 1964 to September 1967. In September 2003, the Veteran submitted the above-captioned service connection claims. After these claims were denied in May 2004, the Veteran perfected an appeal to the Board. The entire adjudicative history need not be repeated here. It is sufficient to state that the Veteran's claims were most recently before the Board in October 2012. At that time, the Board remanded the Veteran's claims for further development. Specifically, the Board found that an October 2011 addendum to a September 2011 VA examination was inadequate. Consequently, the Board directed the RO to obtain another supplemental opinion wherein the examiner addressed the issue of whether the Veteran's diabetes mellitus, type II, was incurred in or due to the Veteran's active duty service for reasons other than his claimed inservice exposure to an herbicidal agent. In November 2012, the RO obtained a supplemental opinion from a VA examiner wherein that issued was thoroughly considered. The RO then re-adjudicated the Veteran's claims, continuing the denial thereof; issued a January 2013 supplemental statement of the case to the Veteran and his representative; and then remitted the Veteran's claims to the Board for further appellate consideration. The Board finds that the RO substantially complied with the directives of the October 2012 remand and, thus, a remand for corrective actions is not required. See Stegall v. West, 11 Vet. App. 268 (1998). As such, the Board will address the merits of the Veteran's claims herein. I. Presumptive Service Connection The law provides that "a veteran who, during active military, naval, or air service, served in the Republic of Vietnam during the period beginning on January 9, 1962, and ending on May 7, 1975, shall be presumed to have been exposed during such service to an herbicide agent...unless there is affirmative evidence to establish that the veteran was not exposed to any such agent during that service." 38 U.S.C.A. § 1116(f) (West 2002). Regulations provide that if a veteran was exposed to an herbicide agent during active service, presumptive service connection is warranted for only the following disorders: Chloracne or other acneform disease consistent with chloracne; Type 2 diabetes (also known as Type II diabetes mellitus or adult-onset diabetes); Hodgkin's disease; chronic lymphocytic leukemia; B cell leukemia, Parkinson's disease, multiple myeloma; non-Hodgkin's lymphoma; acute and subacute peripheral neuropathy; porphyria cutanea tarda; prostate cancer; respiratory cancers (cancer of the lung, bronchus, larynx or trachea); soft-tissue sarcoma (other than osteosarcoma, chondrosarcoma, Kaposi's sarcoma, or mesothelioma); and ischemic heart disease, (including, but not limited to, acute, subacute, and old myocardial infarction; atherosclerotic cardiovascular disease including coronary artery disease (including coronary spasm) and coronary bypass surgery; and stable, unstable and Prinzmetal's angina). 38 C.F.R. § 3.309(e). "Service in the Republic of Vietnam" includes service in the waters offshore and service in other locations if the conditions of service involved duty or visitation in the Republic of Vietnam. 38 C.F.R. § 3.307(a)(6)(iii). Service on a deep-water naval vessel off the shores of Vietnam without proof of actual duty or visitation in the Republic of Vietnam may not be considered service in the Republic of Vietnam for purposes of 38 U.S.C.A. § 101(29)(A) (West 2002). Service in the Republic of Vietnam is interpreted as requiring service on the landmass of Vietnam. Haas v. Peake, 525 F.3d 1168 (Fed. Cir. 2008), cert. denied, 77 U.S.L.W. 3267 (Jan. 21, 2009) (No. 08-525). The evidence of record demonstrates that the Veteran served aboard the U.S.S. Wedderburn and U.S.S. Joseph Strauss during his active duty service. A ship's history and 1966 and 1967 command histories of the U.S.S. Wedderburn were associated with the claims file, but these documents did not demonstrate that the vessel operated within inland waterways or that the Veteran served within the land borders of the Republic of Vietnam. Similarly, a 1968 command history for the U.S.S. Joseph Strauss did not demonstrate that the vessel navigated inland waterways or that the Veteran served within the land borders of the Republic of Vietnam. In a September 2011 letter, the National Archives and Records Administration indicated that, generally speaking, deck logs do not provide information such as the presence of a particular person on a vessel, names of personnel going ashore, or whether a particular person set foot within the land borders of the Republic of Vietnam. As such, the deck logs from the U.S.S. Wedderburn and U.S.S. Joseph Strauss would not serve to establish that the Veteran served within the land borders of the Republic of Vietnam. A newspaper article demonstrated that, while the Veteran served aboard the U.S.S. Joseph Strauss, the vessel was involved in an exchange of fire with land-based installations "near the mouth of the Song Ma River." This article did not demonstrate that the vessel navigated up the river or that the Veteran served within the land borders of the Republic of Vietnam. VA published a list of U.S. Navy vessels of the Vietnam era that are eligible for the presumption of Agent Orange herbicide exposure based on operations of that ship. Included on this list was the U.S.S. Joseph Strauss. However, presumptive service connection was only available for personnel stationed aboard the vessel on March 4, 1966, when it operated on the Mekong River Delta, or on November 7 or December 7, 1966 when it operated in Ganh Rai Bay. The Veteran's service personnel records, particularly his pay records, did not demonstrate that the Veteran served aboard the U.S.S. Joseph Strauss on those dates. Based on the above, the Board finds that there was no official confirmation that the Veteran served within the land borders of the Republic of Vietnam or within the inland waterways. During the pendency of this appeal, the Veteran asserted that, during his service aboard the U.S.S. Wedderburn, the vessel cruised along the coast of Vietnam. He stated that this vessel navigated so close to the shoreline that he could see people and the demilitarized zone, and was close enough that it was subjected to small arms and rocket fire and shellings. Further, the Veteran asserted that the U.S.S. Wedderburn anchored for a brief period in Da Nang harbor. While U.S.S. Wedderburn was anchored, he asserted that he was ordered to utilize a liberty boat to retrieve mail from docks, but denied needing to go ashore to do so. In essence, the Veteran asserted that his military service brought him in close proximity to the land borders of the Republic of Vietnam and, based on this close proximity, presumptive service connection was warranted. However, as discussed above, service on the landmass or on the inland waterways of the Republic of Vietnam is required in order for presumptive service connection to be warranted. Id. Alternatively, the Veteran asserted that the duties associated with his military occupation exposed him to an herbicidal agent. Specifically, the Veteran contended that his service as a Postal Clerk involved handling mail bags that originated in the Republic of Vietnam. He stated that these mail bags were usually dirty or muddy and emitted a "pretty bad" odor, which he claimed was evidence of the presence of an herbicidal agent. While the Board accepts the Veteran's statements as competent and credible evidence that the mail bags were soiled and smelled, there was no evidence of record demonstrating that the Veteran possessed the knowledge, skills, or ability to ascertain the presence of an herbicidal agent. See Layno v. Brown, 6 Vet. App. 465, 469 (1994) (holding that a veteran's statements are competent evidence of what comes to him/her through his/her senses). The Veteran was simply assuming that the condition of the mail bags indicated the presence of an herbicidal agent, which the Board finds is insufficient evidence to establish inservice exposure. Accordingly, the Board finds that the evidence of record was not supportive of finding that the Veteran served within the land borders of the Republic of Vietnam or on inland waterways, and was not otherwise exposed to an herbicidal agent. Consequently, the Board finds that service connection on a presumptive basis for diabetes mellitus, type II, a heart disorder, and bilateral lower extremity peripheral neuropathy is not warranted. 38 U.S.C.A. § 1116(f). Despite this finding, when service connection is not warranted on a presumptive basis, service connection may nevertheless be established on a direct or secondary basis. See Combee v. Brown, 34 F.3d 1039, 1042 (Fed. Cir. 1994). II. Direct and Secondary Service Connection Generally, service connection may be granted for a disability resulting from disease or injury incurred in or aggravated by active military service. 38 U.S.C.A. §§ 1110, 1131; 38 C.F.R. § 3.303. Service connection may also be granted for any disease initially diagnosed after service, when all the evidence, including that pertinent to service, establishes that the disease was incurred during service. 38 U.S.C.A. § 1113(b); 38 C.F.R. § 3.303(d); Cosman v. Principi, 3 Vet. App. 503, 505 (1992). In order to prevail on the issue of service connection there must be medical evidence of a current disability; medical evidence, or in certain circumstances, lay evidence of inservice occurrence or aggravation of a disease or injury; and medical evidence of a nexus between an inservice injury or disease and the current disability. See Hickson v. West, 12 Vet. App. 247, 253 (1999); see also Pond v. West, 12 Vet App. 341, 346 (1999). Service connection may be established on a secondary basis for a disability, which is proximately due to, or the result of a service-connected disease or injury. 38 C.F.R. § 3.310(a). Establishing service connection on a secondary basis requires evidence sufficient to show (1) that a current disability exists and (2) that the current disability was either (a) proximately caused by or (b) proximately aggravated by a service-connected disability. Allen v. Brown, 7 Vet. App. 439, 448 (1995) (en banc). The determination as to whether these requirements are met is based on an analysis of all the evidence of record and the evaluation of its credibility and probative value. See Baldwin v. West, 13 Vet. App. 1, 8 (1999). The evidence of record clearly demonstrated current diagnoses of diabetes mellitus, type II, a heart disorder, and bilateral lower extremity peripheral neuropathy. As determined above, the Board found that the evidence of record was not supportive of finding that the Veteran was exposed to an herbicidal agent during his active duty service on either of presumptive basis or otherwise. As such, the salient issue is whether the Veteran's diabetes mellitus, type II, heart disorder, and bilateral lower extremity peripheral neuropathy is/are shown to be associated with Veteran's military service, to include events, injury, or experiences other than exposure to an herbicidal agent and, as in the case of the Veteran's bilateral lower extremity peripheral neuropathy, whether it was due to or aggravated by a service-connected disability. See Robinson v. Mansfield, 21 Vet. App. 545 (2008) (holding that the Board is not obligated to investigate all possible theories of entitlement). As such, the Board will focus on the evidence of record wherein these issues are addressed. A. Diabetes Mellitus, Type II The Veteran's service treatment records did not demonstrate complaints of or treatment for diabetes mellitus, type II, or symptoms thereof. In a September 2003 letter, Kelly J. Pierce, M.D., essentially opined that the Veteran's diabetes mellitus, type II, was related to his "significant" inservice exposure to Agent Orange. The doctor then stated that, because of the early onset of the Veteran's diabetes mellitus, type II, that it was "more than likely related to his [m]ilitary activities." However, as determined by the Board above, the evidence of record did not demonstrate that the Veteran served within the land borders of the Republic of Vietnam or on the inland waterways and, thus, his exposure to an herbicidal agent during his active duty service will not be presumed. Further, the evidence of record was not otherwise supportive of finding that the Veteran was exposed to an herbicidal agent. As such, to the extent that Dr. Pierce's September 2003 opinion relates the Veteran's current diabetes mellitus, type II, to his inservice exposure to an herbicidal agent, the Board finds that it is predicated on an incomplete or inaccurate factual basis and, thus, is not probative. See Reonal v. Brown, 5 Vet. App. 458, 460-61 (1993). To the extent that Dr. Pierce related the Veteran's diabetes mellitus, type II, to his "military activities," the Board finds that it is insufficient because the doctor did not provide a thorough rationale and did not address all of the relevant evidence of record, including the treatment reports demonstrating the development of obesity many years after the Veteran's service discharge. Nieves-Rodriguez v. Peake, 22 Vet. App. 295, 304 (2008). As such, the Board assigns little to no probative value to this aspect of Dr. Pierce's September 2003 opinion. In February 2010, the Veteran underwent a VA examination. After reviewing of the relevant evidence of record, the examiner observed that the Veteran was first diagnosed with diabetes mellitus, type II, approximately 10 years prior, marking sometime in 2000. Ultimately, the examiner opined as follows: Concerning whether the diabetes...[is] due to exposure to herbicides, this is an issue that the regional office needs to determine, not field examiners. Please refer to the current listing of Agent Orange presumptive conditions. However, it is well known that diabetes is a presumptive condition secondary to Agent Orange. The examiner did not render an opinion as to whether the Veteran's diabetes mellitus, type II, was incurred in or due to his active duty service based on inservice events other than claimed exposure to an herbicidal agent. As such, in January 2011, the Board remanded the Veteran's claim in order to obtain a supplemental opinion. In September 2011, the Veteran underwent another VA examination. In an October 2011 supplemental statement, the examiner reported the following: With respect to the etiology [of the Veteran's diabetes mellitus, type 2], particularly how it may relate to Agent Orange exposure, it is noted that diabetes mellitus, type 2 has been considered a presumptive connection with regard to diagnosis and it association with Agent Orange exposure. This examiner would defer with regard to whether or not this [V]eteran had military exposure to Agent Orange, as this is beyond this examiner's level of expertise. Again, it is noted that Agent Orange exposure has been associated with a diagnosis of diabetes mellitus, type 2. Again, the examiner did not address the issue of whether the Veteran's diabetes mellitus, type II, was incurred in or due to his active duty service based on inservice events other than claimed exposure to an herbicidal agent. Consequently, in October 2012, the Board remanded the Veteran's claim in order to obtain another supplemental opinion. While the Veteran's claim was in remand status, the RO obtained a supplemental opinion dated in November 2012. The examiner opined as follows: Following a review of the evidence of record ...this examiner notes that [V]eteran was released from active military duty in 1967 ([approximately] 21 years of age) and not diagnosed with diabetes mellitus type 2 until the 2000 timeframe when [V]eteran was approximately 54 years of age. Review of [V]eteran's service treatment records notes no evidence of any complaints, symptoms, evaluation, treatment or diagnosis relating to diabetes during his time while on active military duty. This examiner can find no evidence, therefore, to support that [V]eteran's diabetes mellitus type 2 is due to or caused by any illness, injury, event, or other circumstance that may have occurred while on active military duty. Review of [V]eteran's records do [sic] support the fact that this [V]eteran has been diagnosed with obesity, which is significant risk factor for the development of diabetes type 2. Regarding the etiology of this [V]eteran's Type II Diabetes Mellitus (DM II), Up To Date online version notes the following with regard to etiology of DM II: 'Type 2 diabetes mellitus is caused by a combination of varying degrees of insulin resistance and relative insulin deficiency. Its occurrence most likely represents a complex interaction among many genes and environmental factors, which are different among different populations and individuals. The most striking environmental risk factor in most patients who develop type 2 diabetes are increased weight gain and decreased physical activity, each of which increased the risk of diabetes. The mechanism by which obesity induces insulin resistance is poorly understood. Inflammation may be the common mediator linking obesity to the pathogenesis of diabetes.' Based on review of the [V]eteran's clinical presentation and documented evidence of record, it is this examiner's opinion that it is less likely as not that [V]eteran's diabetes mellitus type 2 is causally related to military service. Reasoning and basis for this opinion is that [V]eteran's onset and diagnosis of his diabetes mellitus type 2 did not occur until nearly 33 years following his release from active military duty. Furthermore, [V]eteran does demonstrate evidence of significant risk factors, including environmental risk factors of obesity and decreased physical activity, that most likely contribute most heavily into the etiology of this [V]eteran's diabetes mellitus type 2. It is noted on review of records that evidence of his weight gain and obesity occurred well after his release from active duty, and in no way is likely due to or a result of any illness, injury, event, or other circumstance that may have occurred while on active military duty. In deciding this appeal, the Board must weigh the evidence and decide where to give credit and where to withhold the same and, in so doing, accept certain medical opinions over others. Schoolman v. West, 12 Vet. App. 307, 310-11 (1999). The Board is also mindful that it cannot make its own independent medical determination, and that there must be plausible reasons for favoring one medical opinion over another. Evans v. West, 12 Vet. App. 22, 31 (1998). The Board may favor the opinion of one competent medical expert over that of another provided the reasons therefore are stated. Winsett v. West, 11 Vet. App. 420, 424-25 (1998). For the reasons discussed above, the Board found that Dr. Pierce's September 2003 opinion was of little to no probative value. The only other opinion of record addressing the etiological relationship between the Veteran's diabetes mellitus, type II, and his active duty service, to include inservice events other than exposure to an herbicidal agent, was the VA examiner's November 2012 supplemental opinion. The November 2012 supplemental opinion was preceded by two thorough clinical examinations. Further, the examiner discussed all of the relevant evidence of record and considered the Veteran's non-service related risk factors. As such, the Board finds that the November 2012 VA examiner's opinion is the most probative evidence as to the etiological relationship between the Veteran's current diabetes mellitus, type II, and his active duty service. Schoolman, 12 Vet. App. at 310-11; Winsett, 11 Vet. App. at 424-25. Consequently, the Board is persuaded by the November 2012 VA examiner's opinion and, thus, finds that service connection for diabetes mellitus, type II, is not warranted on a direct basis. B. Heart Disorder The Veteran's service treatment records did not demonstrate complaints of or treatment for a heart disorder or symptoms thereof. In the September 2003 letter, Dr. Pierce also rendered an opinion that the Veteran's heart disorder was related to his "significant" inservice exposure to Agent Orange. The doctor also stated that, because of the early onset of the Veteran's heart disorder, that it was "more than likely related to his [m]ilitary activities." The Board has already assigned little to no probative value to this opinion given the incomplete or incorrect factual basis concerning inservice herbicidal agent exposure and the lack of a thorough rationale wherein all of the relevant evidence was considered, to include post-service events and the Veteran's risk factors. See Reonal, 5 Vet. App. at 460-61; Nieves-Rodriguez, 22 Vet. App. at 304. In February 2010, the Veteran underwent a VA examination. The examiner observed that the onset of the Veteran's heart disorder was sometime in the mid-1980s. After reviewing the relevant evidence of record and administering a thorough clinical examination, the examiner opined as follow: Concerning the heart condition, he appears to have had heart disease present itself at a very young age. He had numerous risk factors for the development of coronary artery disease, including strong family history at a young age. Therefore, his diabetes did not cause his heart disease, and his heart condition is not related to service nor exposure to herbicides nor related to any service-connected disability, because this does not happen, using common medical sense....His heart disease is likely being aggravated by his underlying diabetes, because diabetes is well known to further progress arteriosclerosis, which can easily play into worsening heart disease. This is well known in literature. Unfortunately, there is no testing nor specific methodology that allows us to determine by how much. Otherwise, it does occur and is known to facilitate further vessel change. For the reasons discussed above, the Board found that Dr. Pierce's September 2003 opinion was of little to no probative value. The only other opinion of record addressing the etiological relationship between the Veteran's heart disorder and his active duty service was the VA examiner's February 2010 opinion. The February 2010 opinion was rendered after a review of the relevant evidence of record and a clinical evaluation. The examiner discussed the pertinent evidence of record and considered the Veteran's non-service related risk factors. As such, the Board finds that the February 2010 VA examiner's opinion is the most probative evidence of record as to the etiological relationship between the Veteran's current heart disorder and his active duty service. Schoolman, 12 Vet. App. at 310-11; Winsett, 11 Vet. App. at 424-25. Consequently, the Board is persuaded by the February 2010 VA examiner's opinion and, thus, finds that service connection for a heart disorder is not warranted on a direct basis. Although the February 2010 VA examiner provided a positive opinion with respect to whether the Veteran's heart disorder was aggravated by his diabetes mellitus, type II, as determined above, service connection for the Veteran's diabetes was denied. As such, entitlement to service connection for a heart disorder on a secondary basis is denied as a matter of law. 38 C.F.R. § 3.310(a). Allen, 7 Vet. App. at 448. In making the above determinations, the Board acknowledges that the Veteran asserted that a current heart disorder was related to alleged inservice exposure to asbestos. In support of this assertion, the Veteran submitted an October 2003 statement wherein he claimed that he was exposed to asbestos while serving aboard the U.S.S. Wedderburn. Specifically, the Veteran stated that asbestos was located in floor tiles, was used to wrap piping, and was applied to the walls, among other things. He claimed that he touched and breathed in asbestos. While the Veteran had confirmed service aboard the U.S.S. Wedderburn and U.S.S. Joseph Strauss, there was no official documentation that the Veteran was exposed to asbestos or that he performed a military occupational specialty known to have exposure to asbestos. Indeed, the Veteran's service as a Postal Clerk is inconsistent with exposure to asbestos. The evidence of record included no official service documentation demonstrating that the Veteran was exposed to asbestos, and no clinical opinion relating a current heart disorder to inservice exposure to asbestos. See Jandreau v. Nicholson, 492 F.3d 1372, 1377 (Fed. Cir. 2007) (holding that lay statements are competent evidence of a diagnosis only if they describe symptoms that support a later diagnosis by a medical professional). Further, the evidence did not demonstrate that the Veteran possessed the knowledge, skills, or ability to identify whether or not he was breathing in asbestos. See Layno, 6 Vet. App. at 469. The Veteran simply asserted that he was breathing it in during his active duty service, which the Board finds does not amount to competent evidence of such. Additionally, the Veteran's October 2003 assertions were of record at the time of the February 2010 VA examination. Although the examiner did not specifically articulate an opinion with respect to asbestos, the examiner reviewed the Veteran's claim file and opined that the Veteran's heart disease was not related to his active duty service. Consequently, service connection for a heart disorder, to include as due claimed inservice exposure to asbestos, is not warranted. C. Bilateral Lower Extremity Peripheral Neuropathy The Veteran's service treatment records did not demonstrate complaints of or treatment for bilateral lower extremity peripheral neuropathy. In February 2010, the Veteran underwent a VA examination. The Veteran was unable to mark an approximate date of onset for this disorder, but stated that it was "some years" prior. He described his symptoms as nightly burning sensation in both feet, but no numbness or tingling in either foot. After a thorough clinical examination, the diagnosis was neuropathy of the feet that was etiologically associated with the Veteran's diabetes mellitus, type II. In this, and in other cases, the Board may not base a decision on its own unsubstantiated medical conclusions. Colvin v. Derwinski, 1 Vet. App. 171, 175 (1991). The only competent and probative etiological opinion of record was that of the February 2010 VA examiner, which was negative to the Veteran's claim. Consequently, service connection for bilateral lower extremity peripheral neuropathy is not warranted on a direct basis. While the February 2010 VA examiner provided a positive opinion with respect to whether the Veteran's peripheral neuropathy was associated with his diabetes mellitus, type II, as determined above, service connection for the Veteran's diabetes mellitus, type II, was denied. As such, entitlement to service connection for a bilateral lower extremity peripheral neuropathy on a secondary basis is denied as a matter of law. 38 C.F.R. § 3.310(a). Allen, 7 Vet. App. at 448. D. Additional Considerations and Conclusion During the pendency of this appeal, the Veteran did not assert, and the evidence of record did not support finding, that the he continuously experienced diabetes mellitus, type II, a heart disorder, or bilateral lower extremity peripheral neuropathy since his service discharge. As such, the Board will not address entitlement to service connection for these disorders on the basis of a continuity of symptomatology. 38 C.F.R. § 3.303(b); see Robinson v. Mansfield, 21 Vet. App. 545 (2008). To the extent that the Veteran asserts that his current diabetes mellitus, type II, heart condition, and/or bilateral lower extremity neuropathy is/are related to his active duty service, or were due to or aggravated by a service-connected disability, the Board finds that the matter of the determination of the origin of these disorders, where the credible evidence first demonstrates such disorders many years after service with many potential intervening causes, is more suited to the realm of medical, rather than lay expertise. The precise determination of one etiology when there are several potential origins is too complex for a layperson to proffer a competent opinion, as is the determination that these disorders were aggravated beyond their natural courses by a service-connected disability. The evidence of record does not demonstrate that the Veteran possesses the ability, knowledge, or experience to provide competent etiological opinions or opinions as to aggravation. Jandreau, 492 F.3d at 1377. Consequently, the Veteran's assertions do not constitute competent evidence of etiology or aggravation in this case. Accordingly, service connection for diabetes mellitus, type II, a heart disorder, and bilateral lower extremity neuropathy is not warranted as the most probative evidence shows that these disorder are not related to his military service, to include as due to exposure to an herbicidal agent or asbestos, or due to or aggravated by a service-connected disability. In reaching this decision, the Board considered the doctrine of reasonable doubt; however, as the preponderance of the evidence is against each of the Veteran's claims, the doctrine is not for application. Gilbert v. Derwinski, 1 Vet. App. 49, 58 (1990). ORDER Service connection for diabetes mellitus, type II, to include as due to exposure to an herbicidal agent, is denied. Service connection for a heart disorder, to include as due to exposure to asbestos, to also include as secondary to diabetes mellitus, type II, is denied. Service connection for bilateral lower extremity neuropathy, to include as due to exposure to an herbicidal agent, is denied. ____________________________________________ U. R. POWELL Veterans Law Judge, Board of Veterans' Appeals Department of Veterans Affairs