Institute of Environmental Medicine, Karolinska Institutet, Stockholm, Sweden.
Environ Res. 2011 Nov;111(8):1271-9. doi: 10.1016/j.envres.2011.09.002. Epub 2011 Sep 29.
Little is known about the variation in exposure to toxic metals by age and gender and other potential modifying factors. We evaluated age and gender differences by measurements of metal/element concentrations in urine in a rural population in Matlab, Bangladesh, in three age groups: 8-12 (N=238), 14-15 (N=107) and 30-88 (N=710) years of age, living in an area with no point sources of metal exposure but where elevated water arsenic concentrations are prevalent.
We found marked differences in urine concentrations of metals and trace elements by gender, age, tobacco use, socioeconomic and nutritional status. Besides a clearly elevated urinary arsenic concentration in all age groups (medians 63-85 μg As/L), and despite the low degree of contamination from industries and traffic, the urine concentrations of toxic metals such as cadmium and lead were clearly elevated, especially in children (median 0.31 μg Cd/L and 2.9 μg Pb/L, respectively). In general, women had higher urinary concentrations of toxic metals, especially Cd (median 0.81 μg/L) compared to men (0.66 μg/L) and U (median 10 ng/L in women, compared to 6.4 ng/L in men), while men had higher urinary concentrations of the basic and essential elements Ca (69 mg/L in men, 30-50 years, compared to 52 mg/L in women), Mg (58 mg/L in men compared to 50 mg/L in women), Zn (182 μg/L in men compared to 117 μg/L in women) and Se (9.9 μg/L in men compared to 8.7 μg/L in women). Manganese was consistently higher in females than in males in all age groups, suggesting a biological difference between females and males in Mn metabolism. Increasing socioeconomic status decreased the toxic metal exposure significantly in children and especially in men. Poor iron status was detected in 17% of children, adolescents and women, but only in 6% of men. Also zinc deficiency was more prevalent in females than in males.
Women and children seemed to be more at risk for toxic metal exposure than men and at the same time more vulnerable to micronutrient deficiency. Higher concentrations of the toxic metals in urine in women are likely to reflect an increased gastrointestinal absorption of these metals at micronutrient deficiency, such as low body iron stores and Zn deficiency. Higher urinary concentrations of the essential elements in men likely reflect a better nutritional status. There is a need for information on exposure, lifestyle and socioeconomic factors, stratified by gender and age, for the purpose of conducting balanced risk assessment and management that considers such differences.
关于年龄和性别以及其他潜在调节因素导致的有毒金属暴露差异知之甚少。我们在孟加拉国 Matlab 的一个农村地区，根据尿液中金属/元素浓度，在三个年龄组（8-12 岁，N=238；14-15 岁，N=107；30-88 岁，N=710）评估了年龄和性别差异，该地区没有金属暴露的点状源，但普遍存在高水砷浓度。
我们发现，性别、年龄、吸烟、社会经济和营养状况会导致尿液中金属和微量元素的浓度有明显差异。除了所有年龄组的尿液砷浓度明显升高（中位数 63-85μgAs/L）外，尽管工业和交通造成的污染程度较低，有毒金属（如镉和铅）的尿液浓度也明显升高，尤其是在儿童中（中位数分别为 0.31μgCd/L 和 2.9μgPb/L）。一般来说，女性尿液中的有毒金属浓度高于男性，尤其是镉（女性中位数 0.81μg/L 比男性 0.66μg/L）和铀（女性中位数 10ng/L 比男性 6.4ng/L），而男性尿液中的基础和必需元素钙（男性 69mg/L，30-50 岁，比女性 52mg/L）、镁（男性 58mg/L 比女性 50mg/L）、锌（男性 182μg/L 比女性 117μg/L）和硒（男性 9.9μg/L 比女性 8.7μg/L）浓度较高。所有年龄组的女性锰含量均高于男性，表明女性和男性在锰代谢方面存在生物学差异。随着社会经济地位的提高，儿童，尤其是男性的有毒金属暴露明显减少。在儿童、青少年和妇女中，17%的人缺铁，但只有 6%的男性缺铁。女性缺锌也比男性更为普遍。
女性和儿童似乎比男性更容易受到有毒金属暴露的影响，同时也更容易受到微量元素缺乏的影响。女性尿液中有毒金属浓度较高，可能反映了在微量营养素缺乏（如低体铁储存和缺锌）时，这些金属的胃肠道吸收增加。男性尿液中必需元素浓度较高，可能反映了更好的营养状况。需要按性别和年龄分层，提供有关暴露、生活方式和社会经济因素的信息，以便进行平衡的风险评估和管理，考虑到这些差异。
