Nduka J K C, Orisakwe O E, Maduawguna C A
Pure & Industrial Chemistry Department, Nnamdi Azikiwe University, Awka, Anambra State, Nigeria.
Toxicol Ind Health. 2007 Oct;23(9):525-8. doi: 10.1177/0748233708089038.
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.
对从尼日利亚东部四个主要城市（埃努古、奥尼查、阿巴和哈科特港）的50栋建筑物收集的片状油漆中的镉、铬、铁、锌和铜含量进行了研究。将50个片状油漆样品用实验室研钵和杵研磨，取2克能通过0.5毫米筛网的细磨油漆，与15毫升按1:1比例混合的浓硝酸和高氯酸一起消化，并用原子吸收分光光度计500分析其中的镉、铬、铁、锌和铜。在埃努古，镉含量范围为9.032±0.000至10.575±0.000毫克/千克，在奥尼查为6.845±0.000至10.028±0.002毫克/千克。在阿巴和哈科特港，镉含量分别为7.464±0.002至9.343±0.002毫克/千克和7.293±0.002至9.395±0.000毫克/千克。与其他城市（即奥尼查，含量范围为1.613±0.002至15.140±0.000毫克/千克；阿巴，含量范围为15.206±0.000至39.215±0.000毫克/千克；哈科特港，含量范围为33.118±0.002至55.418±0.002毫克/千克）相比，埃努古的铬含量显著较低（含量范围为0.940±0.000至12.793±0.002毫克/千克）。在埃努古11年及以上的建筑物中，铁（11,908.150±0.000毫克/千克）、锌（31.508±0.002毫克/千克）和铜（7.588±0.002毫克/千克）的含量最高。在奥尼查、阿巴和哈科特港，铁含量（毫克/千克）分别为1391.750±0.000至10,476.845±0.000、1450.176±0.000至11,580.750±0.000和3314.913±0.002至8162.333±0.002。奥尼查的锌含量显著低于阿巴和哈科特港。建筑物的年龄似乎并未影响这些城市中这些金属（即铁、锌和铜）的含量。这项研究表明，片状油漆增加了尼日利亚环境中的重金属负担。
