An intervention to reduce residential insecticide exposure during pregnancy among an inner-city cohort

Abstract

Background: We previously reported widespread insecticide exposure during pregnancy among inner-city women from New York City. Here we report on a pilot intervention using integrated pest management (IPM) to reduce pest infestations and residential insecticide exposures among pregnant New York City African-American and Latina women (25 intervention and 27 control homes).

Methods: The IPM consisted of professional cleaning, sealing of pest entry points, application of low-toxicity pesticides, and education. Cockroach infestation levels and 2-week integrated indoor air samples were collected at baseline and one month postintervention. The insecticides detected in the indoor air samples were also measured in maternal and umbilical cord blood collected at delivery.

Results: Cockroach infestations decreased significantly (p = 0.016) after the intervention among intervention cases but not control households. Among the intervention group, levels of piperonyl butoxide (a pyrethroid synergist) were significantly lower in indoor air samples after the intervention (p = 0.016). Insecticides were detected in maternal blood samples collected at delivery from controls but not from the intervention group. The difference was significant for trans-permethrin (p = 0.008) and of borderline significance (p = 0.1) for cis-permethrin and 2-isopropoxyphenol (a propoxur metabolite).

Conclusion: To our knowledge, this is the first study to use biologic dosimeters of prenatal pesticide exposure for assessing effectiveness of IPM. These pilot data suggest that IPM is an effective strategy for reducing pest infestation levels and the internal dose of insecticides during pregnancy.

Figure 1

Cockroach infestation levels. (A) Mean (± SE) cockroaches (adults + nymphs) in traps collected over 2 weeks pre- (Pre) and postintervention (Post). Intervention group: preintervention (n = 22), post-intervention (n = 19); control group: preintervention (n = 14), postintervention (n = 6). (B) Percent reduction between total cockroaches in traps collected over 2 weeks pre- and postintervention. Intervention (n = 19), control (n = 6). Comparison of differences in percent reduction in pest infestation levels between the intervention and control groups, group t-test, p = 0.1 (B). *Wilcoxon signed-rank test, p = 0.016.

Figure 2

Piperonyl butoxide in 2-week integrated air samples. (A) Changes in mean (± SE) piperonyl butoxide levels in 2-week integrated indoor air samples collected over 2 weeks before and 2 weeks after the intervention. Intervention (n = 23), control (n = 24). (B) Percent reduction in piperonyl butoxide levels between 2-week integrated indoor air samples collected over 2 weeks before and 2 weeks after the intervention. Intervention (n = 23), control (n = 24). Comparison of differences in percent reduction in piperonyl butoxide levels between the intervention and control groups, group t-test, p = 0.3) (B). *Wilcoxon signed-rank test, p = 0.016.