1. Kennedy, Maureen Shawn MA, RN

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Chronic exposure to low levels of environmental chemicals can harm a developing fetus, and although the adverse effects on a child are sometimes obvious, often they don't appear until years later, according to two recent reports.

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Organic solvents in the work-place.

Most organic solvents can be inhaled and absorbed through skin. According to Canadian researchers, occupational exposure of pregnant women to organic solvents is associated with specific neurodevelopmental problems in their children, even when protective equipment is used. A group of 32 pregnant women who were exposed to organic solvents at work (most commonly toluene, xylene, ethanol, and acetone) were matched with a control group of 32 pregnant women who were not exposed. The women had a diverse array of occupations-laboratory technician, factory worker, graphic designer, embalmer, chemist, hair stylist, and science teacher, among others. Some were exposed to many different chemicals simultaneously. All were exposed to organic solvents during the first trimester. Exposure occurred over at least eight weeks, with the duration of exposure ranging from one to 40 hours per week. The women used protective equipment most of the time.


When given a battery of neuropsychological tests at age three or four years, the children of the women who had been exposed to organic solvents showed significant deficits in manual dexterity and visual-motor integration. Their rate of hyperactivity was more than three times that of children born to women in the control group. The degree of exposure to organic solvents didn't matter.


This study suggests that the use of standard protective equipment may not protect the developing fetus. The authors recommend that employers improve ventilation in work settings or assign pregnant women to areas away from organic solvents. Providers must counsel pregnant women and those planning pregnancy on the possible risks of chemical exposures at work.


Hydrocarbons and tobacco smoke in an urban environment.

Polycyclic aromatic hydrocarbons are attached to the tiny particles produced by the combustion of diesel and other fuels, such as that used in automobiles and heating plants, and can be inhaled deeply. Researchers conducted a prospective study to examine the effect of maternal exposure to these compounds on the development of respiratory problems in children; they also examined whether environmental tobacco smoke exacerbated the problem.


To monitor exposure to the hydrocarbons, researchers gave air monitors to 303 pregnant women living in Harlem or South Bronx, which they wore for 48 hours during the third trimester. Exposure to environmental tobacco smoke was determined through a questionnaire and by levels of cotinine in plasma and cord blood at birth. Complete follow-up data after two years were available for 169 of the children (42% of whom were exposed to tobacco smoke).


Many children experienced respiratory symptoms, defined as coughing, breathing difficulty, wheezing, and "probable asthma." More than 40% experienced cough, and about 15% suffered from breathing difficulty, wheezing, or probable asthma. Prenatal hydrocarbon exposure, by itself, didn't increase the risk of respiratory symptoms, and prenatal exposure to environmental tobacco smoke increased the odds of cough only, by about 36%.


Prenatal hydrocarbon exposure plus postnatal exposure to tobacco smoke, however, increased the odds of breathing difficulty by about 54%, the odds of wheezing by about 44%, and the odds of probable asthma by about 64%. This interaction was statistically significant only in boys; why girls appear to be protected, at least at two years of age, isn't known. Postnatal hydrocarbon exposure wasn't measured-it's possible that it, rather than prenatal exposure, was responsible for the interaction with exposure to postnatal tobacco smoke.


Family members of young children should be informed of the effects of environmental tobacco smoke on a child's respiratory health and offered smoking-cessation support. -Fran Mennick, BSN, RN


Laslo-Baker D, et al. Arch Pediatr Adolesc Med 2004;158(10):956-61;Miller RL, et al. Chest 2004;126(4):1071-8.