Nitric oxide and superoxide anion production in monocytes from children exposed to arsenic and lead in region Lagunera, Mexico

• Published in: Toxicology and applied pharmacology 2004-08, Vol.198 (3), p.283-290
• Main Authors: Pineda-Zavaleta, Ana Patricia, Garcı́a-Vargas, Gonzalo, Borja-Aburto, Victor H, Acosta-Saavedra, Leonor C, Vera Aguilar, Eunice, Gómez-Muñoz, Arı́stides, Cebrián, Mariano E, Calderón-Aranda, Emma S
• Format: Article
• Language: English
• Subjects: Arsenic; Arsenic - adverse effects; Arsenic - blood; Arsenic - immunology; Biological and medical sciences; Chemical and industrial products toxicology. Toxic occupational diseases; Child; Children; Cross-Sectional Studies; Environmental Pollutants - adverse effects; Environmental Pollutants - blood; Environmental Pollutants - immunology; Female; Humans; Immunotoxicity; Interferon-gamma - pharmacology; Lead; Lead - adverse effects; Lead - blood; Lead - immunology; Lipopolysaccharides - pharmacology; Male; Medical sciences; Metals and various inorganic compounds; Mexico; Monocytes - drug effects; Monocytes - immunology; Monocytes - metabolism; Nitric oxide; Nitric Oxide - biosynthesis; Superoxide; Superoxides - metabolism; Toxicology
• ISSN: 0041-008X; 1096-0333
• DOI: 10.1016/j.taap.2003.10.034

We evaluated in Mexican children environmentally exposed to arsenic and lead monocyte nitric oxide (NO) and superoxide anion production in response to direct activation with interferon-γ (IFN-γ) + lipopolysaccharide (LPS). The integrity of Th1-regulated cellular immune response when monocytes were indirectly activated was also evaluated. Most children lived near a primary lead smelter. Lead and arsenic contamination in soil and dust by far exceeded background levels. As levels in water were between 10 and 30 ppb. Most children (93%) had urinary arsenic (AsU) concentrations above 50 μg/l (range 16.75–465.75) and 65% had lead blood levels (PbB) above 10 μg/dl (range 3.47–49.19). Multivariate analyses showed that NO production in monocytes activated indirectly was negatively associated with both PbB and AsU. Superoxide production in directly activated monocytes was negatively associated with AsU but positively associated with PbB. The models including the interaction term for AsU and PbB suggested the possibility of a negative interaction for NO production and a positive interaction for superoxide. There were indications of differential gender-based associations, NO production in indirectly activated monocytes obtained from girls was negatively associated with AsU but not with PbB. Superoxide production was positively associated with PbB in both directly and indirectly activated monocytes from boys but the latter was negatively associated with AsU. These effects are consistent with immune system abnormalities observed in human populations exposed to Pb or As. Further studies in larger populations are required to characterize As and Pb interactions and the mechanism(s) underlying the observed effects.