Changes in human serum antioxidant capacity and peroxidation after four months of exposure to air pollutants

Twenty-one adult volunteers (aged 27-32 years), who had been living in Mexico City for four continuous months (physicians working as fellows) were studied the first and sixteenth week of their stay in order to learn the effect of the pollutants contained in Mexico City's atmosphere on some serum biochemical parameters. The activity of serum superoxide dismutase (SOD) decreased after 16 weeks in comparison with the values obtained the first week (109.6 to 56.9 mU/mg protein; 50 percent less). In contrast, the inhibitory capacity of serum vs. induced in vitro lipoperoxidation increased in relation to the length of stay (22 percent). The serum levels of thiobarbituric-reactive material also decreased in almost 30 percent (from 6.10 to 4.12 nmol). The other lipoperoxides measured were unchanged (chromolipids and diene conjugation). We propose that this may be as a result of the adaptive capacity of the human orgnaisms, within a pollutant atmosphere in which the ozone levels might participate in a decrease of SOD activity during chronic exposure, to air pollution

Possible effect of air pollutants (Mexico City) on superoxide dismutase activity and serum lipoperoxides in the human adult

The action of air pollutants, through their constituents, (O3, NO2, tobacco smoke) are capable of causing damage due to their lipoperoxidative properties or, indirectly, by inducing production of free radicals. As a consequence of photochemical processes, the ozone levels in the atmosphere of Mexico City are generally higher (mean of 0.325 ppm; period between 1987 - 1992) and may be harmful to health. Sixty two volunteers (medical doctors), aged 27-32 years, were divided into three groups. Group A was composed of those persons /17) who had never lived in Mexico City; a second group (B) (21) had recently arrived in Mexico City (1-8 days); and a third group (C) (24) who had permanently resided in mexico City. Serum was obtained from fresh whole blood. Superoxide dismutase (SOD) activity and thiobarbituric acid-reactive materials were higher in group B while chromolipids and the serum inhibitory capacity (for lipoperoxidation) was higher in group C. The acute exposure to pollutants in group B apparently may have induced SOD as an antioxidant defense and was responsible for the increased level of TBA reactive material. In group C, the significant finding is better antioxidative defenses and slightly higher chromolipids