Aluminum and Zinc levels in water from two towns having different water sources and treatment systems in São Paulo State

DOI: 10.15343/0104-7809.200630.4.13

Abstract

Ground water treatment requires fluoridation and chlorination processes. In water from superficial sources, the treatment is based on flocculation,
filtering, fluoridation and chlorination. Aluminum sulfate is used as a flocculant agent in this kind of treatment, which may increase this metal
concentration in water. Aluminum (Al) has been related to Alzheimer Disease (AD). Zinc (Zn) is also a very important metal for human health, especially
for senior populations. The objective of this study is to compare the concentrations of Al and Zn in potable water processes, considering different sources
of water collecting and treatment. Water samples of two cities in Sao Paulo State were analyzed: Ribeirão Preto, supplied with ground water, and Atibaia,
supplied with superficial water. Fifty samples of potable water were collected from faucets in homes of senior people and retirement houses. The values
found for Al showed that 24% of samples from Ribeirão Preto exceeded the maximum allowed values by national regulations, whereas values found in
Atibaia were within allowed values. Zinc levels were under the maximum established values, in both cities, but the statistical test pointed at a significant
difference between them (p<0,0001), showing increased concentrations in Ribeirão Preto. The detection of metals above normalized values represents a
risk for the health of the population and is important as information in the Public Health context, considering the toxicity of metals for human health.
Future studies to verify the quality of public water supplies are extremely necessary.