Considerations for occupational risk management during pregnancy: A summary of a continuing education course.

Women comprise approximately 40% of the global workforce, and many women continue to work during pregnancy. Although occupational exposure limit values (OELVs) are intended to protect all workers, many OELVs may have been established without consideration of the unique changes in pregnant workers, and many chemicals lack OELVs altogether. A short educational course was developed to address the informational needs of health professionals who have responsibility to ensure a safe workplace for pregnant employees.

Extended one-generation reproductive toxicity study of food-grade titanium dioxide E171 with emphasis on reproductive and endocrine endpoints.

Food-grade titanium dioxide E171 was administered in feed to Sprague Dawley rats in an extended one-generation reproductive toxicity (EOGRT) study (OECD Test 443). The dosed diet (0, 100, 300, or 1000 mg/kg body weight/day) started 10 weeks before mating and continued throughout the study. After weaning, pups were allocated to Cohorts 1 A/1B (to assess reproductive toxicity), 2 A/2B (to assess developmental neurotoxicity), and 3 (to assess developmental immunotoxicity); in addition, Cohort 1B was mated to produce an F generation and satellite F animals were evaluated for colonic aberrant crypt foci (ACF).

A critical look at adjusted fetal weights in rats.

Background: A new derived (i.e., calculated) endpoint of developmental toxicology has appeared in a very few studies since 1990.

Revisiting the testicular toxicity of cyanide: Assessment of the new and existing literature.

Background: Based on new testing, we re-assess U.S. EPA and California OEHHA conclusions regarding male reproductive toxicity associated with cyanide exposure.

Comparative anatomy, pre- and postnatal changes during the development and maturation of the small intestine: Life-stage influences on exposure.

The gastrointestinal (GI) system absorbs nutrients and xenobiotics, excretes waste, and performs immunologic and endocrine functions. The subdivisions of the mature gut and the complexity of their corrugated, absorptive luminal surfaces differ greatly among mammals. Regardless, the embryonic gut tube in all mammalian species arises when cephalocaudal folding incorporates the roof of the yolk sac into the embryo.

Systematic assessment of quaternary ammonium compounds for the potential to elicit developmental and reproductive effects.

Introduction: Quaternary ammonium compounds (QUATs) are commonly found in cleaning products, disinfectants, hand sanitizers, and personal care products. They have been used for >50 years and are considered safe when used according to directions. Recent papers report reduced fertility and neural tube defects in rodents after low-level exposures.

Teratogen update: Topical use and third-generation retinoids.

The first pharmaceutical retinoids approved by the U.S. Food and Drug Administration were given black-box warnings against their use in pregnancy due to potential teratogenic effects.

Of embryos and tumors: Cyclopia and the relevance of mechanistic teratology.

Embryos and tumors share several characteristics, but embryos differ from tumors in their coordination of cellular- and tissue-level processes, including organized differentiation, remodeling of tissues through apoptosis, and disciplined migrations of cells. Embryonic cellular events are kept on track through orderly cell-cell communication via signal transduction pathways. If the pathways are disrupted, development is perturbed, and malformation may result.

Trichloroethylene in drinking water throughout gestation did not produce congenital heart defects in Sprague Dawley rats.

Background: Trichloroethylene (TCE) was negative for developmental toxicity after inhalation and oral gavage exposure of pregnant rats but fetal cardiac defects were reported following drinking water exposure throughout gestation. Because of the deficiencies in this latter study, we performed another drinking water study to evaluate whether TCE causes heart defects.

Methods: Groups of 25 mated Sprague Dawley rats consumed water containing 0, 0.

The arrogance of teratology: A brief chronology of attitudes throughout history.

While the discipline of Teratology has existed for about 60 years, there has been a deep interest in the causes of human malformations for millennia. Absent the scientific method and acting on fervent beliefs that made sense to ancient/medieval populations, "mechanisms" were described and prognostications of future events were assigned to terata resulting in tragic (and unwarranted) sequelae. This article examines the collective beliefs and thinking within various eras in the hope of providing lessons to inform future behavior.

Impact of chloroform exposures on reproductive and developmental outcomes: A systematic review of the scientific literature.

Aims: We assessed the animal and epidemiological data to determine if chloroform exposure causes developmental and/or reproductive toxicity.

Results And Discussion: Initial scoping identified developmental toxicity as the primary area of concern. At levels producing maternal toxicity in rats and mice, chloroform caused decrements in fetal weights and associated delays in ossification.

Bone development in laboratory mammals used in developmental toxicity studies.

Evaluation of the skeleton in laboratory animals is a standard component of developmental toxicology testing. Standard methods of performing the evaluation have been established, and modification of the evaluation using imaging technologies is under development. The embryology of the rodent, rabbit, and primate skeleton has been characterized in detail and summarized herein.

Vascular ontogeny within selected thoracoabdominal organs and the limbs.

The cardiovascular system is fundamental to life. Its vessels are the conduits for delivery of nutrients and oxygen to organs and the removal of wastes. During embryonic development, the vascular system is instrumental in the formation of organs.

In utero arsenic exposure in mice and early life susceptibility to cancer.

In its review of the U.S. Environmental Protection Agency's toxicological review of inorganic arsenic (iAs), the National Academy of Sciences identified carcinogenic endpoints among the highest priority health effects of concern and stated the need to consider evidence that early life exposures may increase the risk of adverse health effects.