An occupational reproductive research agenda for the third millennium.

Abstract

There is a significant public health concern about the potential effects of occupational exposure to toxic substances on reproductive outcomes. Several toxicants with reported reproductive and developmental effects are still in regular commercial or therapeutic use and thus present potential exposure to workers. Examples of these include heavy metals, organic solvents, pesticides and herbicides, and sterilants, anesthetic gases, and anticancer drugs used in health care. Many other substances are suspected of producing reproductive or developmental toxicity but lack sufficient data. Progress has been limited in identifying hazards and quantifying their potencies and in separating the contribution of these hazards from other etiologic factors. Identifying the causative agents, mechanisms by which they act, and any potential target populations, present the opportunity to intervene and protect the reproductive health of workers. The pace of laboratory studies to identify hazards and to underpin the biologic plausibility of effects in humans has not matched the pace at which new chemicals are introduced into commerce. Though many research challenges exist today, recent technologic and methodologic advances have been made that allow researchers to overcome some of these obstacles. The objective of this article is to recommend future directions in occupational reproductive health research. By bridging interdisciplinary gaps, the scientific community can work together to improve health and reduce adverse outcomes.

Environmental Toxicants Induced Male Reproductive Disorders: Identification and Mechanism of Action

“…Both isoforms of recombinant human estrogen receptor and human androgen receptor are commercially available for this purpose. Based on the same principles, other batteries of high-throughput assays are available to screen for activity against various receptors and cytochrome P-450 enzyme isoforms (Lawson et al, 2003). The availability and application of these assays will undoubtedly expand as we understand more about the relevance of each protein in toxicologic processes.…”

“…Understanding mechanisms of action of toxicants is important for a number of reasons, including a) supporting the biologic plausibility of an observed association between chemical exposure and adverse outcome; b) uncovering common pathways of actions of different agents; c) extrapolating across species for risk assessment; d) improving the predictability of human morbidity from responses of model species; and e) predicting responses to mixed exposures (Lawson et al, 2003). Mechanistic studies are not new in toxicology; however, new tools in genomics, proteomics, and bioinformatics present unprecedented opportunities to advance our understanding of toxicant action at a molecular level.…”

Maternal Recognition of Pregnancy

“…The addition of biological markers of reproduction and semen characteristics, along with evaluation for use of occupational exposure data from existing sources (e.g., birth certificates) are potential activities to enhance human surveillance. 29 Surveillance of reproductive health findings across multiple studies may also be conducted in the form of systematic reviews or meta-analyses, such as multinational efforts to monitor for the existence of declines in men's sperm counts.…”

Fertility preservation: state of the science and future research directions

“…People with DNA-repair deficiencies are also more susceptible to gonadotoxicity. Some people are at risk for impaired fertility or infertility because of exposure to occupational or environmental hazards and thus might want to take measures to preserve their fertility (11,12). For example, some industries, particularly textiles, clinical laboratories, manufacturing, printing, and dry cleaning, frequently involve exposure to chemical hazards.…”