Rowbotham A L, Levy L S, Shuker L K
MRC Institute for Environment and Health, University of Leicester, United Kingdom.
J Toxicol Environ Health B Crit Rev. 2000 Jul-Sep;3(3):145-78. doi: 10.1080/10937400050045255.
Chromium in the hexavalent form, Cr(VI), has long been recognized as a carcinogen and there is concern as to the effects of continuous low-level exposure to chromium both occupationally and environmentally. This review summarizes the available exposure data and known health effects and evaluates the potential risk to human health in the United Kingdom. Chromium emissions to the environment in the United Kingdom are predominantly derived from fuel combustion, waste incineration, and industrial processes. The less toxic trivalent form of chromium [Cr(III)] is dominant in most environmental compartments, and any Cr(VI), the more toxic form, that is emitted to the environment can be reduced to Cr(III). Food is a major source of exposure to chromium, and estimated daily oral intakes for infants (1 yr), children (11 yr), and adults are 33-45, 123-171, and 246-343 micrograms/person/d, respectively. Soil ingestion, particularly common in young children, can contribute to oral intake. Inhalation is a minor route of exposure for the general population. Average daily inhalation intakes in infants can range from 0.004 microgram/d for rural infants to 0.14 microgram/d for urban infants who are passively exposed to tobacco smoke, whereas adults who live in industrialized areas and smoke may take up between 2 and 12 micrograms/d. The most serious health effect associated with Cr(VI) is lung cancer, which has been associated with some occupational exposure scenarios, whereas Cr(III) is an essential nutrient with a broad safety range and low toxicity. The human body has effective detoxification mechanisms that can reduce ingested or inhaled Cr(VI) to Cr(III). In conclusion, there is no clear evidence to relate exposure to environmental levels of chromium with adverse health effects in either the general UK population or subgroups exposed to chromium around industrialized or contaminated sites. It can be expected that an improved understanding of the relevance of possible long-term accumulation of Cr(III) in the body may facilitate a more complete assessment, in the future, of the health risks in the general population associated with environmental exposure to chromium.
六价铬（Cr(VI)）长期以来一直被认为是一种致癌物，人们担心职业和环境中持续低水平接触铬的影响。本综述总结了现有的接触数据和已知的健康影响，并评估了英国对人类健康的潜在风险。英国向环境中的铬排放主要来自燃料燃烧、废物焚烧和工业过程。毒性较小的三价铬[Cr(III)]在大多数环境介质中占主导地位，排放到环境中的毒性更强的Cr(VI)可以还原为Cr(III)。食物是接触铬的主要来源，婴儿（1岁）、儿童（11岁）和成年人的估计每日口服摄入量分别为每人每天33 - 45微克、123 - 171微克和246 - 343微克。土壤摄入在幼儿中尤为常见，可能会增加口服摄入量。吸入是一般人群接触铬的次要途径。婴儿的平均每日吸入摄入量范围从农村婴儿的0.004微克/天到被动接触烟草烟雾的城市婴儿的0.14微克/天，而生活在工业化地区且吸烟的成年人可能每天摄入2至12微克。与Cr(VI)相关的最严重健康影响是肺癌，这与一些职业接触情况有关，而Cr(III)是一种必需营养素，安全范围广且毒性低。人体有有效的解毒机制，可以将摄入或吸入的Cr(VI)还原为Cr(III)。总之，没有明确证据表明英国一般人群或工业化或受污染场地周围接触铬的亚组人群接触环境水平的铬会对健康产生不良影响。预计未来对Cr(III)在体内可能长期积累的相关性有更深入的了解，将有助于更全面地评估一般人群中与环境接触铬相关的健康风险。
