Lead levels in paint flakes from buildings in Nigeria: a preliminary study.

Lead is a malleable metal previously used to improve the durability and color luster of paint applied in homes and on industrial structures such as bridges. Lead has deleterious effects on multiple organs in humans. There is paucity of information on the extent of the use of lead-based paint in Nigerian houses. This study has attempted to estimate the extent of use of lead-based paint in buildings in Eastern Nigeria using 168 buildings. Flaked paint samples were collected from residential, church, commercial, and school buildings from four most populous cities in Eastern Nigeria namely Enugu, Onitsha, Aba, and Port Harcourt, and they were digested using conc HNO(3):HCLO(4) (1:1) and analyzed using atomic absorption spectrophotometer. The lead levels from buildings in Enugu ranged from 39.385 +/- 1.111-69.843 +/- 4.886 mg/kg. The highest level of lead was found in Onitsha ranging from 49.503 +/- 0.000-74.352 +/- 0.571 mg/kg. Residential buildings, which mainly serve the under privileged populations, has the highest lead level in this study. In Aba, the highest lead level (66.432 +/- 0.013 mg/kg) was found in commercial buildings aged 5-10 years. The lead levels in paint flakes from buildings in the four cities tended to decrease with increasing age of the buildings. Taken together all the building paint flakes from the four cities had lead levels higher than the United States Environmental Protection Agency permissible level of 5 mg/kg. There is a need for primary intervention strategy to reduce the paint lead levels in Nigeria.

Acid rain phenomenon in niger delta region of Nigeria: economic, biodiversity, and public health concern.

Rain samples were collected from Warri and Port Harcourt, two major oil-producing cities of Nigeria in April-June, July-August, and September-October 2005 and 2006. Awka, a "non-oil" city was used as control. Samples were collected from three points, using clean plastic basins fastened to a table, 2 m above ground level and 115 m away from tall buildings and trees. Water samples were filtered and acidity determined using digital pH meter. The results show that the rain samples were acidic. The pH values for the 2 years under study show that the rainfall in Warri was more acidic than that of Port Harcourt. Oil exploration and other anthropogenic sources may be responsible for the acid rain in the Niger Delta region of Nigeria.

Heavy metal levels and physico--chemical quality of potable water supply in Warri, Nigeria.

The interaction between man's activities and the environment is gaining world wide attention. Warri an oil producing community in Delta State of Nigeria is faced with environmental oil pollution. Since open and underground water bodies are regarded as final recipients of most environmental pollutants, this study sought to provide data on the levels of the physico-chemical parameters and contaminants in Warri metropolitan water supply. This study investigated the cadmium, lead and chromium using Atomic Absorption Spectrophotometer, physico-chemical properties such as pH, temperature, total suspended solid TSS, total dissolved solid TDS, electrical conductivity EC, biological oxygen demand BOD, dissolved oxygen DO, chemical oxygen demand COD, and total coliform count of potable water sources in Warri. Ekpan River was found to have 1.2 mg/L of cadmium, 1.0 mg/L of chromium, 1.20 mg/L of lead and 2.0 mg/L of manganese. The heavy metals levels and the pollution parameters were lowest in the borehole water samples, except pH which is more acidic in borehole water samples and conductivity which is more in well water samples in all the sampling stations. Some of the parameters were above WHO standards.

Heavy metals other than lead in flaked paints from buildings in Eastern Nigeria.

Cadmium, chromium, iron, zinc, and copper levels of flaked paints collected from fifty buildings of four major cities - Enugu, Onitsha, Aba, and Port Harcourt in Eastern Nigeria were studied. Fifty samples of the flaked paints were ground with laboratory pestle and mortar, 2 g of fine ground paints that could pass through a 0.5-mm sieve were digested with 15 ml concentrated nitric acid and perchloric acid at a ratio of 1:1 and analyzed for cadmium, chromium, iron, zinc and copper using atomic absorption spectrophotometer 500. Cadmium ranged from 9.032 +/- 0.000 to 10.575 +/- 0.000 and 6.845 +/- 0.000 to 10.028 +/- 0.002 mg/kg in Enugu and Onitsha, respectively. In Aba and Port Harcourt, the levels of cadmium ranged 7.464 +/- 0.002-9.343 +/- 0.002 and 7.293 +/- 0.002-9.395 +/- 0.000 mg/kg, respectively. Chromium levels were significantly lower in Enugu (range 0.940 +/- 0.000-12.793 +/- 0.002 mg/kg) when compared with the values from other cities namely Onitsha (range 1.613 +/- 0.002-15.140 +/- 0.000 mg/kg), Aba (range 15.206 +/- 0.000-39.215 +/- 0.000 mg/kg) and Port Harcourt (range 33.118 +/- 0.002-55.418 +/- 0.002 mg/kg). The highest levels (mg/kg) of iron (11,908.150 +/- 0.000), zinc (31.508 +/- 0.002) and copper (7.588 +/- 0.002) were seen in buildings from Enugu aged 11 years and above. The iron level (mg/kg) ranged from 1391.750 +/- 0.000 to 10,476.845 +/- 0.000, 1450.176 +/- 0.000 to 11,580.750 +/- 0.000 and 3314.913 +/- 0.002 to 8162.333 +/- 0.002 in Onitsha, Aba, and Port Harcourt, respectively. Zinc levels were significantly lower in Onitsha than in Aba and Port Harcourt. Age of building did not seem to affect the levels of these metals namely iron, zinc and copper from these cities. This study shows that flaked paints increase the environmental heavy metal burden in Nigeria.