Quality characteristics of rainwater around an industrial area in Warri, Delta State, Nigeria

Petroleum crude oil refining to generate useful products releases noxious gases such as sulphur (IV) oxide, nitrogen (IV) oxide and carbon (IV) oxide, which dissolve in rainwater to form acid rain. This research was to ascertain the impact of the refining process on the rainwater quality in a peri-urban area where residents depend on precipitation for domestic use, including cooking. Rainwater samples were collected from some locations in close proximity to a refinery in Warri and characterized in terms of physico-chemical parameters, and heavy metals proximal contents using methods recommended by America Public Health Association. For the period under study, results revealed that pH was relatively low in all the rainwater samples. Mean pH values obtained ranged from 4.20 ± 0.17 to 6.24 ± 0.04. Turbidity values ranged between 2.00 ± 0.20 NTU and 12.5 ± 0.83 NTU. Although the levels of heavy metals notably, lead, copper, cadmium and zinc were low, total iron was slightly significant in some samples. Water with low pH values and high heavy metal concentrations could adversely affect water bodies, aquatic life, soils, plants and cause lots of aesthetic damage to structures. Similarly, possible percolations into underground water aquifers can affect humans that use such water, including rainwater for most domestic uses.