Identification and characterization of trace metals in black solid materials deposited from biomass burning at the cooking stoves in Bangladesh

In this study we have reported the emissions of trace metals from biomass burning at the cooking stoves. Black solid materials deposited from two different types of biomass (rice husk coils - type 1; mixed (straw, bamboo, cow dung, leaves and plants) biomasses - type 2) burning at the cooking stoves were collected from the top of the stoves (but inside the roof of the kitchen) in Narsingdi, Dhaka, Bangladesh. Systematic chemical analysis was done for both samples. Lead, mercury, iron and calcium were identified in sample type-1, and lead, iron and magnesium were identified in sample type-2. The concentration of the trace element was determined with an atomic absorption spectrophotometer. The average concentrations of lead, iron, cadmium calcium, potassium and magnesium were 95.6, 11520, 8.33, 1635, 17.1 and 443.1 mg kg(-1), respectively in sample type-1. The average concentration of lead, iron, cadmium calcium, potassium and magnesium were 125.2, 12360, 12.0, 1648, 21.5 and 534.2 mg kg (1), respectively in sample type-2. However, the average concentrations of the determined trace elements followed the sequences, Fe > Ca > Mg > Pb > K > Cd. The emission of lead, iron, cadmium, calcium, potassium and magnesium were much higher from mixed biomass (type-2) compared than the rich husk coils (type-1). The mixed biomass produced about 31% higher lead, 44% higher cadmium, 26% higher potassium, and 21% higher magnesium compared than the rice husk coils. This is the first systematic analysis for the trace metal emissions from different types of biomass burning at the cooking stoves in Bangladesh. (C) 2009 Elsevier Ltd. All rights reserved.