Chronic arsenic exposure and risk of infant mortality in two areas of Chile.

Abstract

Chronic arsenic exposure has been associated with a range of neurologic, vascular, dermatologic, and carcinogenic effects. However, limited research has been directed at the association of arsenic exposure and human reproductive health outcomes. The principal aim of this study was to investigate the trends in infant mortality between two geographic locations in Chile: Antofagasta, which has a well-documented history of arsenic exposure from naturally contaminated water, and Valparaíso, a comparable low-exposure city. The arsenic concentration in Antofagasta's public drinking water supply rose substantially in 1958 with the introduction of a new water source, and remained elevated until 1970. We used a retrospective study design to examine time and location patterns in infant mortality between 1950 and 1996, using univariate statistics, graphical techniques, and Poisson regression analysis. Results of the study document the general declines in late fetal and infant mortality over the study period in both locations. The data also indicate an elevation of the late fetal, neonatal, and postneonatal mortality rates for Antofagasta, relative to Valparaíso, for specific time periods, which generally coincide with the period of highest arsenic concentration in the drinking water of Antofagasta. Poisson regression analysis yielded an elevated and significant association between arsenic exposure and late fetal mortality [rate ratio (RR) = 1.7; 95% confidence interval (CI), 1.5-1.9], neonatal mortality (RR = 1.53; CI, 1.4-1.7), and postneonatal mortality (RR = 1.26; CI, 1.2-1.3) after adjustment for location and calendar time. The findings from this investigation may support a role for arsenic exposure in increasing the risk of late fetal and infant mortality.ImagesFigure 1Figure 2Figure 3Figure 4Figure 5

Effect of Topical Dimethylarsinic Acid on the Expression of Apoptosis-Related Proteins in Mouse Skin

“…Even though the mRNA level of caspase-12 was slightly increased with the treatment of DMA, the expressions of other genes and proteins, including the protein expression of caspase-12, were not significantly changed. Although exposure to arsenic during pregnancy is known to negatively affect the offspring (Hopenhayn-Rich et al 2000), our results suggest that fetal exposure to DMA did not alter the expression of apoptosis-related proteins in the skin. There are a number of possible explanations for this finding.…”

Exploring chronic arsenic poisoning in pre-Columbian Chilean mummies

“…Natural water sources, particularly in the Camarones valley located about 100 km south of the modern city of Arica, have arsenic levels 100 times higher than the 10 mg/L normal limit recommended by the World Health Organization. Chronic arsenic poisoning produces a myriad of health problems ranging from premature birth, stillbirths, neonatal death, skin disorders, growth arrest, neurological disorders and various types of cancer (Ahmad et al, 2001;Hopenhayn-Rich et al, 2000;Nordströ m et al, 1979). In addition, arseniasis causes teratogenic anomalies such as cleft palate and neural tube defects including spina bifida to name a few (Ahmad et al, 2001;Centeno et al, 2002;Hood, 1972).…”

Toxicology and Epidemiology of Arsenic and its Compounds

“…In humans, following exposure to arsenic in the drinking water, adverse pregnancy outcomes, such as spontaneous abortion, still births, preterm birth rates, low birth weight, and increased infant mortality have been reported (Ahmad et al, 2001;Hopenhayn-Rich, 2000). Ahmad et al (2001) conducted a cross-sectional study of woman of reproductive age in Bangladesh.…”

“…In the exposed population that had been drinking water containing levels of arsenic > 0.05 mg L −1 for at least five years, there was a significantly greater adverse pregnancy outcome than the nonexposed population (As < 0.02 mg L −1 ). In a retrospective study of infant mortality in two cities of Chile with a high (Antofagasta) and low (Valparaiso) exposure to arsenic in drinking water, Hopenhayn-Rich et al (2000) reported a significant association between arsenic exposure and late fetal mortality (rate ratio (RR) = 1.7), neonatal mortality (RR = 1.53), and postnatal morality (RR = 1.26) after adjustment for location and calendar time. Overall, additional studies need to be conducted to investigate this potential relationship between arsenic in utero exposure and development effects in humans.…”