研究證實 兒時接觸鉛污染與成年暴力犯罪有關 | 台灣環境資訊協會-環境資訊中心

研究證實 兒時接觸鉛污染與成年暴力犯罪有關

2008年06月02日
摘譯自2008年5月28日ENS美國,俄亥俄州辛辛那提報導,吳萃慧編譯,蔡麗伶審校

孩童時期的血液鉛濃度與暴力行為被逮捕率的關聯性最高。圖片來源:FBI胎兒時期及稚齡兒童血液中的高鉛濃度首次被拿來與其成年之後較高犯罪被逮率進行聯想。新的研究中顯示,孩童時期的血液鉛濃度與犯罪行為中因暴力行為被逮捕率的關聯性最高。

辛辛那提大學戴爾崔屈(Kim Dietrich)博士及他的研究團隊根據他們在辛辛那提市對兒童時期體內鉛濃度的長期研究資料,發表產前及兒童期初期鉛曝露量與其在人生較晚期犯罪行為增加風險直接關聯性的首次證據。

身為這個研究團隊主持人以及該校環境衛生學教授的戴爾崔屈解釋:「先前的許多研究有些是依據間接的測量方式,有些則沒有繼續追蹤受試者至成年階段來檢驗其成人初期犯罪行為與鉛曝露量的關聯性」。

他表示:「我們持續監測這個受試兒童次群體在子宮階段到孩童期初期鉛曝露狀況已有30年了,我們有一套神經學的、行為的及發育的模式的完整紀錄,用來對生命初期鉛曝露量與其成年後犯罪活動作清楚的關聯分析」。
兒童可經由吃進含鉛的塗料碎片或在受鉛污染的土壤上玩耍而接觸到鉛,而鉛會損害神經、腎臟及生殖系統。戴爾崔屈指出:「侵略性或暴力行為模式常常都是在人生階段早期就開始了,並且常會持續至終身,因此確認出會致使年輕人在人生初期就陷入終身犯罪與暴力的危險因子,應該被列為公共衛生議題的優先順位。」

一群工人正在移除含鉛的油漆。圖片來源:ENS戴爾崔屈表示,僅有很少數的研究曾試圖評估兒童時期鉛曝露量導致犯罪行為的前後關係。

這個研究的共同作者芮艾特博士(John Wright)表示,他過去對鉛曝露量與犯罪行為之間關聯強度的期望並沒有太高。芮艾特是辛辛那提大學犯罪懲戒系統成員之一,他進行犯罪行為的遺傳、心理及生物學因子研究,在初期也對這個理論抱持懷疑態度。

他表示:「我當時並不預期能夠看到任何作用,別說是明確的效應,甚至還覺得不會有任何高度反應的作用。事實卻證明我們現在可以偵測兒童時期鉛曝露狀況到成年階段的作用,這成為顯示鉛能夠長期影響行為的一項強而有力的明證。」

Childhood Lead Exposure Linked to Violent Crime in Adults
CINCINNATI, Ohio, May 28, 2008 (ENS)

High levels of lead in the blood of fetuses and young children has been linked for the first time to higher rates of criminal arrest in adulthood. The strongest association between childhood blood-lead level and criminal behavior was for arrests involving acts of violence, new research has found.

Based on long-term data from a childhood lead study in Cincinnati, Kim Dietrich, PhD, and his team at the University of Cincinnati found the first evidence of a direct link between prenatal and early-childhood lead exposure and an increased risk for criminal behavior later in life.

"Previous studies either relied on indirect measures of exposure or failed to follow subjects into adulthood to examine the relationship between lead exposure and criminal activity in young adults," explains Dietrich, principal investigator of the study and professor of environmental health at the University of Cincinnati.

"We have monitored this specific sub-segment of children who were exposed to lead both in the womb and as young children for nearly 30 years," he says.

"We have a complete record of the neurological, behavioral and developmental patterns to draw a clear association between early-life exposure to lead and adult criminal activity," says Dietrich.

Children can be exposed from eating lead-based paint chips or playing in contaminated soil. Lead can damage the nervous system, kidneys, and reproductive system.

"Aggressive or violent behavioral patterns often emerge early and continue throughout life," Dietrich says. "Identifying the risk factors that may place youth on an early trajectory toward a life of crime and violence should be a public health priority."

Dietrich says few studies have attempted to evaluate the consequences of childhood lead exposure as a risk of criminal behavior.

Study coauthor John Wright, PhD says he had limited expectations for how strong a correlation between lead exposure and criminality could be established. A member of the university’s criminal justice faculty who studies the impact of factors like genetics, psychology and biology on criminality, Wright was a skeptic at first.

"I did not expect we would see an effect, much less a substantive effect and even less likely a highly resilient effect," says Wright. "The fact that we are able to detect the effects from childhood exposures now into adulthood stands as a testament of lead’s power to influence behavior over a long period of time."

At four prenatal clinics between 1979 and 1984, the researchers recruited pregnant women living in Cincinnati neighborhoods with a higher concentration of older, lead-contaminated housing.

Of the original 376 newborns recruited, 250 were tracked for the current study. Dietrich’s team has monitored this group of children since birth to assess the long-term health effects of early-life lead exposure.

Researchers measured blood-lead levels during pregnancy and then at regular intervals until the children were six and a half years old to calculate cumulative lead exposure.

Blood-lead level data was correlated with public criminal arrest records from a search of Hamilton County, Ohio criminal justice records.

全文及圖片詳見:ENS