The potential of exposure biomarkers in epidemiologic studies of reproductive health.

Abstract

To further the development and application of exposure markers in field investigations in reproductive epidemiology, we have synthesized recent examinations of the issues surrounding exposure measurements in reproductive epidemiology. The specific goals of this paper are to define exposure biomarkers and explore their potential uses, particularly as screening tools. The tests for glucaric acid, thioethers, mutagenicity, and porphyrin patterns meet the general criteria for useful exposure screens. For certain xenobiotic agents, these tests accurately differentiate exposure levels, as demonstrated in occupational and environmental epidemiologic studies. As urinary screens, they are noninvasive and applicable on a large scale with current laboratory techniques. For short-term exposure, glucaric acid, thioethers, and mutagenicity tests are useful. Porphyrin patterns may measure cumulative effects as well as current exposure levels. The usefulness of these tests in epidemiologic studies of environmental effects on reproductive health has yet to be studied. To do so, the battery must be standardized for pregnant women, and test results must be correlated with measured adverse reproductive outcomes, such as gestational length and birthweight. This correlation is particularly important because maternal exposure rather than fetal exposure is being measured. The extent to which xenobiotic chemicals cross the placental barrier may vary greatly depending on the type of exposures, timing in pregnancy, and maternal detoxification capability. Without better exposure measures, epidemiologic studies of reproductive health probably will not successfully identify xenobiotic fetotoxic agents in the environment. However, with an adequate battery of nonspecific exposure biomarkers, prospective studies of environmental effects on pregnancy outcomes might be possible.(ABSTRACT TRUNCATED AT 250 WORDS)

Biological monitoring of workers exposed to N-nitrosodiethanolamine in the metal industry.

“…However, we did not find any association between NDELA exposure and urinary DGA. This finding was not entirely unexpected because DGA excretion has been found to increase after exposure to some chemicals, such as pesticides, but not to styrene, dioxin, or toluene (36). In a previous study by our group, no increase was found in steel-plant workers exposed to mineral oils with respect to controls (40).…”

“…In a previous study by our group, no increase was found in steel-plant workers exposed to mineral oils with respect to controls (40). A high intraindividual variation in DGA excretion has been described, which may reflect both genetic and environmental factors and may explain these contradictory results (36). We found an association between coffee drinking and DGA urinary values in this study, which suggests that factors other than occupational exposure can influence urinary DGA excretion, and they should therefore be taken into account in occupational and environmental studies.…”

“…many DNA-damaging agents, including alkylating agents, can be detoxified through glucuronidation as a major route (36,38,39). However, we did not find any association between NDELA exposure and urinary DGA.…”

Evaluation of health risks for contaminated aquifers.

“…The characterization of health risk variability for homogeneous and heterogeneous populations is very important information that is needed to develop and evaluate fully the effectiveness and performance of remediation technologies to reduce health risks for the least cost. In this regard, greater use of biological indicators of exposure and disease in epidemiological studies may be an important research activity to continue and to expand (152)(153)(154)(155)(156).…”

Application of Biologic Markers to Studies of Environmental Risks in Children and the Developing Fetus

“…The use of biologic markers in molecular epidemiologic studies of fetal and childhood exposures can circumvent some of these limitations. To date, biologic markers have not been widely used in developmental epidemiology of environmental exposures (16,17); however, they offer the potential to provide quantitative dosimeters of biologic dose and/or indices of biologic effect associated with fetal and childhood exposures to environmental carcinogens and other toxicants. Further, they can facilitate quantification of differences in the magnitude of response in the young relative to that in adults.…”