Volume 3 • Issue 2 • 1000178 J Environ Anal Chem ISSN: 2380-2391 JREAC, an open access journal Kabamba et al., J Environ Anal Chem 2016, 3:2 DOI: 10.4172/2380-2391.1000178 Research Article Open Access Toxic Heavy Metals in Ambient Air of Kinshasa, Democratic Republic Congo Kabamba M 1 , Basosila N 1 , Mulaji C 1 , Mata H 1 and Tuakuila J 1,2 * 1 Environmental Health, Medical and Analytical Chemistry, Faculty of Sciences, University of Kinshasa, Kinshasa, Democratic Republic of Congo 2 Louvain Center for Toxicology and Applied Pharmacology (LTAP), Université catholique de Louvain, Brussels, Belgium Keywords: Ambient air; Heavy metals; Air pollution; Public health; Kinshasa Introduction Heavy metals are ubiquitous in the environment. Teir presence occurs in both natural and anthropogenic forms. While usually natural forms are present at relative low concentrations, in recent years a number of anthropogenic sources such as dumping of waste, smelter stacks, waste incineration, vehicle exhausts, fertilizers, agricultural waste, and sewage sludges have implied notable contributions to the increase of environmental metal concentrations [1-4]. With the development of mining, smelting and other industrial activities, heavy metals are increasingly being found in the environment which can pose severe threats to human and environmental health. Pollution by heavy metals such as arsenic (As), cadmium (Cd), lead (Pb) afects the quality of the atmosphere and the soil as well as water bodies and threatens the health and life of animals and human beings by way of the food chain [5-9]. Developing countries are confronted with the great challenge of controlling the atmospheric pollution, especially in the rapidly growing megacities. Concern about air pollution in urban regions is receiving increasingly importance worldwide, especially pollution by trace metals. Te Democratic Republic of Congo (DRC) is particularly rich in natural resources and eastern provinces (Katanga and Kivu) have been the center of extensive mining exploitation. Bas-Congo, close to Kinshasa, also contains a wide variety of mineral species. But, Kinshasa is not considered to be a mining zone. Te demography in Kinshasa, the largest city in DRC, has exploded in the recent years [10]. Te congested trafc with the widespread use of motorbikes as well as old automobiles coupled with poor maintenance, inadequate infrastructure, and low fuel quality is an important source of outdoor pollution. Wood, charcoal, crop, residual oil, and waste residues combustion for heating and cooking in open fres or poorly functioning stoves are the main source of indoor air pollution [11,12]. Trough a study carried out to assess the exposure to trace elements in urine of the Kinshasa population, [13] showed elevated levels of Al, As, Cd, Pb and Hg as compared to other databases. But little documented information exists concerning diferent sources of trace element exposures in Kinshasa. Te present study originated from that observation and its main objective was to investigate background levels of As, Cd, Pb and Ni in ambient air samples from Kinshasa. Materials and Methods Description of locations and sample collection in Kinshasa Kinshasa, the capital city of DRC, is located in the west of the country with an area of 9,965 km². Te city is split into 4 districts with more than ten million of residents. Kinshasa has a tropical climate with two seasons: rainy and dry. Te dry season extends from 15 May to 15 August. Te rainy season can be taken the remaining period. An air sample is taken over a 24-hour period, every six days from each of three following sites: roadside sites, residential sites and sub- rural sites. Sample sites are given in Figure 1. Sample collection was done using a high volume sampler on quartz fbre flter according to Australian Standard AS 3580.9.6-1990 Method [14]. All samples were transported in a box to be analyzed at the Louvain Centre for Toxicology and Applied Pharmacology (LTAP, Brussels, Belgium). Te samples were mineralized in a microwave preparation system (A Paar Multiwave V3.20.5): each flter was digested with 5 ml of nitric acid (65% Suprapur, E. Merck, Darmstadt, Germany) in Tefon vessel for 0.3 min (A paar Multiwave V 3.20.5). Afer digestion, solutions were fltered and made up to 25 ml with nanopur water. Laboratory blanks were prepared by using nitrocellulose flters and treating it in the same way as the samples. Element analysis Four elements (As, Cd, Pb and Ni) were quantifed by inductively coupled argon plasma mass spectrometry (ICP-MS Agilent 7500 CE). Briefy, 0.50 mL sample was diluted with 4.50 mL of diluent (1% v/v HNO 3 , 0.5% v/v HCl and 50 ppb Sc, Ge, Rh, and Ir as internal standards (IS)). Matrix-matched calibrators were prepared by adding 0.05 mL of a calibration standard into 0.45 mL of acid (1% v/v HNO 3 and 0.5% v/v HCl) and 4.5 mL of diluent. Both acids, HCl and HNO 3 , were of *Corresponding author: Tuakuila J, Louvain Center for Toxicology and Applied Pharmacology (LTAP), Université catholique de Louvain, Brussels, Belgium, Tel: 234819347828; E-mail: joeltuakuila@yahoo.fr Received March 17, 2016; Accepted April 11, 2016; Published April 25, 2016 Citation: Kabamba M, Basosila N, Mulaji C, Mata H, Tuakuila J (2016) Toxic Heavy Metals in Ambient Air of Kinshasa, Democratic Republic Congo. J Environ Anal Chem 3: 178. doi:10.41722380-2391.1000178 Copyright: © 2016 Kabamba M, et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. Abstract The particularly high rate of urbanization in Kinshasa is associated with environmental degradation, such as air pollution. However, little documented information exists on the nature and extent of this pollution. In the present study, Atmospheric samples of ambient air were collected in Kinshasa for 4 months (July to October, 2009) and analyzed for As, Cd, Pb and Ni using ICP - MS. The ranges of heavy metal concentrations for the 24-h ambient air samples in roadside sites (residential sites) were 0.9-6.0 ng/m 3 (0.4-2.8 ng/m 3 ), 2.5-5.9 ng/m 3 (1.2-3.5 ng/m 3 ), 166.2-1422.5 ng/m 3 (72.0-1685.0 ng/m 3 ), 48.7-482.0 ng/m 3 (42.0-117.6 ng/m 3 ) for As, Cd, Pb and Ni, respectively. Current 24-h average levels of all of them show higher levels than those measured in Europe. Toxicologically relevant elements reach levels of public health concern. The Efforts should be made to reduce the levels of metal contamination. J o u r n a l o f E n v ir o n m e n t a l A n a l y t i c a l C h e m i s t r y ISSN: 2380-2391 Journal of Environmental Analytical Chemistry