夢幼森林

以下摘譯自: 美國食品暨藥物管理局網頁的

疫苗保存劑硫柳汞(乙基汞)的毒性Thimerosal Toxicity

http://www.fda.gov/BiologicsBloodVaccines/SafetyAvailability/VaccineSafety/UCM096228#thi

各種汞的指引是根據流行病學和實驗室研究甲基汞而來，而硫柳汞是一種乙基汞的衍生物。

The various mercury guidelines are based on epidemiological and laboratory studies of methyl mercury, whereas thimerosal is a derivative of ethyl mercury. 因為-乙基與甲基汞-是不同的化學實體並期望應有不同的毒性理論。Because they are different chemical entities - ethyl- versus methylmercury - different toxicological profiles are expected.因此，把甲基汞的毒理應用到硫柳汞，出現了不確定性。缺乏明確的數據，比較乙基汞與甲基汞的相對毒性， There is, therefore, an uncertainty that arises in applying the methylmercury-based guidelines to thimerosal. Lacking definitive data on the comparative toxicities of ethyl- versus methylmercury, 美國食品暨藥物管理局認為應把乙基汞當做甲基汞來做風險評估。FDA considered ethyl- and methyl-mercury as equivalent in its risk evaluation. 在本節的總結有一些直接關係到硫柳汞的毒性數據和研究。There are some data and studies bearing directly on thimerosal toxicity and these are summarized in this Section.

臨床文獻中描述硫柳汞的過敏性反應，主要是以局部遲緩型過敏反應形式表現出來，包括在注射部位有紅腫反應(Cox and Forsyth 1988; Grabenstein 1996).。Allergic responses to thimerosal are described in the clinical literature, with these responses manifesting themselves primarily in the form of delayed-type local hypersensitivity reactions, including redness and swelling at the injection site (Cox and Forsyth 1988; Grabenstein 1996). 這種注射部位有紅腫反應通常都是輕微的，只有持續幾天。一些作者推測，硫柳酸鹽（thiosalicylate）的成分是過敏反應的主要決定因素(Goncalo et al. 1996)。【硫柳汞屬於乙基汞(ethylmercury)類衍生物，故在人體可代謝為乙基汞及硫柳酸鹽 (thiosalicylate) 而排除。】   Such reactions are usually mild and last only a few days. Some authors postulate that the thiosalicylate component is the major determinant of allergic reactions (Goncalo et al. 1996). 在臨床上，但是，無法確定局部反應的原因是否主要是硫柳汞或其他疫苗成分引起。In a clinical setting, however, it is usually not possible to determine whether local reactions are caused by thimerosal or other vaccine components.

最早發表人類使用硫柳汞的報告是在1931年(Powell and Jamieson 1931).。

The earliest published report of thimerosal use in humans was published in 1931 (Powell and Jamieson 1931). 在這份報告中，有22人靜脈滴注1％的硫柳汞溶液，治療原因不詳。

In this report, 22 individuals received 1% solution of thimerosal intravenously for unspecified therapeutic reasons. 受試者注射高達26毫克硫柳汞/公斤（1毫克等於1000微克），沒有毒性作用報告，雖然二個人顯現局部浸潤後靜脈炎或皮膚脫落， Subjects received up to 26 milligrams thimerosal/kg (1 milligrams equals 1,000 micrograms) with no reported toxic effects, although 2 subjects demonstrated phlebitis or sloughing of skin after local infiltration. 值得注意的是，這項研究並非專為檢查毒性; 7/22受試者只有觀察一天，具體的臨床評估是沒有描述，也沒有實驗室研究的報告。Of note, this study was not specifically designed to examine toxicity; 7 of 22 subjects were observed for only one day, the specific clinical assessments were not described, and no laboratory studies were reported.

從醫學文獻中，發現的幾例含硫柳汞產品的急性汞中毒，硫柳汞的總劑量範圍從大約3毫克/公斤到幾百毫克/公斤。 Several cases of acute mercury poisoning from thimerosal-containing products were found in the medical literature with total doses of thimerosal ranging from approximately 3 mg/kg to several hundred mg/kg. 這些報告包括使用免疫球蛋白（γ球蛋白）These reports included the administration of immune globulin (gamma globulin) (Matheson et al. 1980) 與B肝免疫球蛋白and hepatitis B immune globulin (Lowell et al. 1996), 以氯黴素與1000倍適當劑量的硫柳汞作為藥物保存劑的配製。choramphenicol formulated with 1000 times the proper dose of thimerosal as a preservative (Axton 1972), 使用於兒童中耳管含硫柳汞的灌洗液(Rohyans et al. 1994)， thimerosal ear irrigation in a child with tympanostomy tubes (Rohyans et al. 1994),治療嬰幼兒臍帶突出缺陷的硫柳汞 thimerosal treatment of omphaloceles in infants (Fagan et al. 1977), 和企圖用硫柳汞自殺and a suicide attempt with thimerosal (Pfab et al. 1996). 這些研究報告有：局部壞死，急性溶血，瀰漫性血管內凝血，急性腎小管壞死，中樞神經系統損傷包括機能衰鈍，昏迷和死亡。（美國醫學研究所IOM）

These studies reported local necrosis, acute hemolysis, disseminated intravascular coagulation, acute renal tubular necrosis, and central nervous system injury including obtundation, coma, and death. (IOM)

幾種動物的硫柳汞毒性研究評估。在1931年鮑威爾Powell和賈米森Jamieson在一些動物物種的硫柳汞急性毒性研究報告。Several animal studies have evaluated the toxicity of thimerosal. In 1931 Powell and Jamieson reported acute toxicity studies in several animal species. 動物不致死的硫柳汞最大耐受劑量：兔子是20毫克/公斤和老鼠是45毫克/公斤。Maximum tolerated doses not associated with death of the animals were 20 mg thimerosal/kg (rabbits) and 45 mg/kg (rats). 布萊爾(Blair)評估硫使用柳汞滴鼻液190天，觀察大腦或腎並沒有組織病變。 Blair evaluated the administration of thimerosal intranasally for 190 days and observed no histopathological changes in the brain or kidney (Blair et al. 1975). 馬戈斯等（Magos et al.）直接以成年雄性和雌性大鼠，每天灌胃餵食5天劑量的等摩爾濃度的乙基汞或甲基汞，來比較乙基汞與甲基汞的毒性，（馬戈什等Magos et al 1985）。directly compared the toxicity of ethyl- versus methylmercury in adult male and female rats administered 5 daily doses of equimolar concentrations of ethyl- or methylmercury by gavage (Magos et al 1985). 馬戈斯Magos的結論，依汞的各種衍生物指引，乙基汞的衍生物硫柳汞是比甲基汞的神經毒性少。 Magos concluded that ethylmercury, the mercury derivative found in thimerosal, is less neurotoxic than methylmercury, the mercury derivative for which the various guidelines are based.

最後一件硫柳汞資料是值得注意的。One final piece of data regarding thimerosal is worth noting. 在1999年，在最初的國家疫苗諮詢委員會主辦的硫柳汞會議上，有人擔心，嬰兒可能沒有能力排除乙基汞。 At the initial National Vaccine Advisory Committee-sponsored meeting on thimerosal in 1999, concerns were expressed that infants may lack the ability to eliminate mercury. 更多最近的美國國家過敏與傳染病研究所（NIAID）資助在羅切斯特大學的研究和在馬里蘭州貝塞斯達Bethesda的國家海軍醫療中心研究，從接受常規含硫柳汞疫苗免疫接種的嬰兒，採集血液檢體，檢驗嬰兒血液中汞的濃度。More recent NIAID-supported studies at the University of Rochester and National Naval Medical Center in Bethesda, MD examined levels of mercury in blood and other samples from infants who had received routine immunizations with thimerosal-containing vaccines. [Pichichero ME, et al. Lancet 360:1737-1741 (2002)] 在這些研究中，所有嬰兒血液中的汞濃度不超過甲基汞對嬰幼兒安全指引。

Blood levels of mercury did not exceed safety guidelines for methyl mercury for all infants in these studies. 此外，汞從接受含硫柳汞疫注的嬰兒血液中比預期的甲基汞更快速排除;

Further, mercury was cleared from the blood in infants exposed to thimerosal faster than would be predicted for methyl mercury; 嬰兒接受含硫柳汞疫注後，從糞便將他們的體內的汞大量地排出。infants excreted significant amounts of mercury in stool after thimerosal exposure, thus removing mercury from their bodies. 這些結果顯示，硫柳汞和甲基汞是有不同方式的分佈，代謝和排泄。

These results suggest that there are differences in the way that thimerosal and methyl mercury are distributed, metabolized, and excreted. 硫柳汞似乎比甲基汞更快速從體內血液中排除。

Thimerosal appears to be removed from the blood and body more rapidly than methyl mercury. 美國國家過敏與傳染病研究所（NIAID）正贊助在布宜諾斯艾利斯(Buenos Aires)較多的嬰兒仍接受含硫柳汞疫注後的追蹤研究。

 NIAID is sponsoring a follow-up study with larger numbers of infants in Buenos Aires where thimerosal-containing vaccines are still administered to children. 見下面“相關鏈接”找到一個鏈接到美國國家衛生研究院（NIH） / 美國國家過敏與傳染病研究所（NIAID）的疫苗/硫柳汞的網站。 See "Related Links" below to find a link to the NIH/NIAID vaccines/thimerosal web site.

資料摘譯自: 美國食品暨藥物管理局網頁

http://www.fda.gov/BiologicsBloodVaccines/SafetyAvailability/VaccineSafety/UCM096228#thi

參考資料：

1. 搜尋疫苗受害者-美國國家疫苗資訊中心 Search Vaccine Victims – NVIC

http://www.nvic.org/Vaccine-Memorial/Search-Memorial.aspx

2.硫柳汞與疫苗。http://www.who.int/vaccine_safety/topics/thiomersal/zh/index.html

3.自閉症－含汞疫苗惹的禍？康健雜誌2007。99:136~141。

4.在疫苗的硫柳汞Thimerosal in Vaccines. http://www.fda.gov/cber/vaccine/thimfaq.htm

5.汞(硫柳汞)和疫苗Mercury and Vaccines (Thimerosal) http://www.cdc.gov/od/science/iso/concerns/thimerosal.htm

6.美國國家疫苗資訊中心National vaccine lnformation Center http://www.nvic.org/

7.美國醫學研究所(IOM)  http://www.iom.edu/CMS/3793/4705/4717.aspx

8.美國國家過敏與傳染病研究所（NIAID），美國國家衛生研究院（NIH）。