On the Forefront of Disaster
The NIEHS has been a key part of the federal response to the 11 September 2001 attacks on the World Trade Center. The NIEHS News (p. A526) tells how the institute is helping to safeguard the health of workers in the recovery effort, as well as the surrounding communities.
Environmental Aftermath
There are many questions to ask in the wake of the World Trade Center terrorist attacks. Some of these questions have to do with environmental health. The Focus (p. A528) asks, what are the immediate and long-term health effects of the million-plus tons of steel, dust, smoke, and debris that fell from the World Trade Center? How can they be combatted? And what happens next?
A United Front against Bioterrorism?
Two months before terrorists attacked in New York City and Washington, DC, the United States was the only country to reject a recently developed protocol to strengthen the Biological and Toxin Weapons Convention. The Spheres of Influence (p. A538) describes the convention and discusses why the United States rejected the protocol--and whether the country might change its mind at the upcoming Fifth Review Conference of the State Parties to the Convention.
Sensitivity of the Rodent Uterotrophic Assay
Ashby (p. 1091) comments on the rodent uterotrophic assay and the data available for bisphenol A and concludes that uterine weight is still a good method for determining the estrogenicity of environmental contaminants. He suggests that dose-reponse studies that include the no-observed-effect level should be conducted to clarify the criteria for the individual markers of toxicity by comparing the end points of morphometric or molecular changes to the gravimetric end point.
Bioavailability of Octamethylcyclotetrasiloxane
Luu and Hutter (p. 1095) developed a physiologically based pharmacokinetic (PBPK) model to predict target organ doses of octamethylcyclotetrasiloxane (D4) after intravenous, inhalation, or implantation exposures. The model predicted bioaccumulation of D4 in fatty tissues; because of its high lipid solubility , D4 persisted in fat for several days after breast implant exposure. This model should be useful for the risk assessment of D4 in women exposed daily to personal care products and silicone breast implants.
Immunoassay for Hexamethylene Diisocyanate
Lemus et al. (p. 1103) developed a sensitive and specific immunoassay to detect recent hexamethylene diisocyanate (HDI) exposure. The most sensitive bioassay was a three-antibody sandwich with a sensitivity of 1.8 nM HDI. Compared with current methods for HDI detection, the immunoassays are faster and less costly, and accommodate numerous samples simultaneously.
Chlorpyrifos Transfer from Dog Fur
Boone et al. (p. 1109) estimated the amount of residues that children might obtain from dogs treated with a flea and tick dip containing chlorpyrifos. The authors investigated the time course or dissipation of residues after treatment, the influence of different fur length on transferable residues, and the effect of bathing dogs between dips. The cotton glove dosimeter method will be useful in determining transferable residues from other pesticide exposures. (Also see Science Selections, p. A543)
Bone Lead Measured by XRF or AAS
Todd et al. (p. 1115) used 109Cd-based K-shell X-ray fluorescence (XRF) to measure lead in swine femurs and to validate the concentrations against measurements of bone lead using atomic absorption spectrometry (AAS). The XRF spectrum peak extraction method may require adjustment because, on average, XRF overestimated AAS-measured femur lead by 2.6 µg/g.
Dump Site Housing and Disease
Pukkala and Ponka (p. 1121) investigated whether exposure to a landfill causes cancer or other chronic diseases in those living in a contaminated area in Helsinki, Finland. Using a cohort of 2,000 persons who had ever lived in houses built on the dump area and a reference cohort, the authors determined that there were some increases in cancer incidence and in chronic diseases in those living in proximity to the dump site. The possibility of a causal association between dump exposure and incidence of cancer and asthma could not be excluded.
Paternal Exposure to Dioxin Posed No Risk of Maternal Abortion
Schnorr et al. (p. 1127) studied pregnancy outcomes among wives of men who were exposed to chemicals contaminated with TCDD during the production of sodium trichlorophenol or one of its derivatives and among wives of nonexposed men who lived in the same area. Although men who were exposed to TCDD while working in U.S. factories were exposed to TCDD at levels hundreds of times higher than TCDD levels in the general population, there was no association between paternal serum TCDD level and spontaneous abortion in this population.
Breast-Feeding and PBBs Unrelated
Thomas et al. (p. 1133) examined the relationship between serum measurements of polybrominated biphenyls (PBBs) and the frequency and duration of lactation. Persons who lived on or received food from farms exposed to PBBs participated in a survey of reproductive outcomes. The intervals or the total duration of breast-feeding were not significantly associated with serum PBB levels, even after controlling for potential confounders.
Individual Lead Concentrations in Human Bones
Todd et al. (p. 1139) examined the variability and differences between core and surface tibia lead concentrations in 10 adult human cadaver legs. The authors found that these human tibiae showed a greater concentration of surface tibia lead than core tibia lead, which may affect evaluation of the noninvasive measurement of tibia lead via K-shell and L-shell X-ray fluorescence.
Metabolism of Growth Promoters in Cattle
Trenbolone (TbA) and melengestrol acetate (MGA) are growth promoters used in farm animals in several meat-exporting countries. Schiffer et al. (p. 1145) examined the residues and degradation of TbA and MGA and determined hormone residues in manure from treated cattle and in soil from fields fertilized with manure. The authors found that TbA and MGA were detectable long after soil fertilization, suggesting these substances could have potential endocrine-disrupting activity in agricultural ecosystems.
Aroclor 1254 Lots Differ in Toxicity
Kodavanti et al. (p. 1153) compared the biological effects of two lots of Aroclor 1254 after analyses for polychlorinated biphenyl congeners, polychlorinated dibenzofurans, naphthalenes, or dibenzodioxins. Although analytically they differed only slightly, there were significant differences in neuronal responses to the two lots of Aroclors, indicating that the composition of Aroclor mixtures used in research investigations should be determined.
Differential Toxicity of Two Lots of Aroclor 1254
In an examination of the congener composition of two lots of Aroclor 1254 used in toxicity studies, one lot had approximately 10 times the dioxin toxic equivalents (TEQ) of the other. Burgin et al. (p. 1163) determined that the differences in the TEQs of the two lots explain the differences in the strict dioxin-like effects in vivo, but that non-dioxin-like congeners cause other effects that are not associated with the aryl hydrocarbon receptor. The authors stress that the lot numbers of Aroclor 1254 are necessary because the congener composition, and therefore the effects observed, can be very different.
Neurotoxic Effects of Exposure to Sarin in Humans
Nishiwaki et al. (p. 1169) conducted a cross-sectional epidemiologic study on the rescue team and police officers 3 years after the Tokyo subway sarin attack. The authors performed neurobehavioral stabilometry and vibration perception threshold tests, as well as psychometric tests, to assess traumatic stress symptoms. In a test of memory function, the exposed group performed less well in the backward digit span test than the unexposed group in a dose-effect manner. The authors suggest that sarin may have caused a chronic decline of memory function because other tests of memory were also affected, although to a lesser extent. (Also see Science Selections, p. A542)
Hypospadias: A Congenital Male Reproductive Anomaly
Hypospadias (abnormal development of the urethra or penis) is a common congenital anomaly in the United States that occurs in about 1 of 125 live male births. Surgery is the only treatment, so prevention is imperative. Baskin et al. (p. 1175) discuss the normal development of the male external genitalia and the prevalence, etiology, risk factors, and epidemiology of hypospadias. (Also see Science Selections, p. A542)
Distribution of 2,4-D in Homes after Lawn Applications
Nishioka et al. (p. 1185) collected indoor air, surface wipes, and floor dust samples at multiple locations within 11 occupied homes and 2 unoccupied homes before and after lawn application of the herbicide 2,4-D. The major source of 2,4-D in indoor air was resuspension of floor dust, with the highest levels of 2,4-D found in the particle size range of 2.5-10 µm. Estimated postapplication indoor exposure levels for young children from nondietary ingestion are estimated to be about 10 times higher than preapplication exposures.
Last Updated: November 12, 2001
