Personal and indoor exposure to PM2.5 and polycyclic aromatic hydrocarbons in the southern highlands of Tanzania: a pilot-scale study

Abstract

Personal and indoor exposure to PM(2.5) and polycyclic aromatic hydrocarbons (PAHs) were measured in households in the Njombe district of Tanzania. Cooking is conducted indoors in this region due to its high elevation, cool climate, and heavy seasonal rainfall. Kitchens are often poorly ventilated, resulting in high exposures to combustion-related pollutants. Sampling sites were selected to represent typical cooking practices across regional socio-economic divisions. These include the use of open wood fires, charcoal, a mix of charcoal and kerosene, and liquid petroleum gas (LPG) for cooking fuels. PM(2.5) average personal exposure was 14 μg/m(3) (±3, n = 3) for LPG, 88 μg/m(3) (±42, n = 3) for kerosene/charcoal mix, 588 μg/m(3) (±347, n = 3) for charcoal alone, and 1574 μg/m(3) (±287, n = 3) for open wood fires. Total PAH average personal exposures were less than 1 ng/m(3) (±1, n = 3) for LPG, 57 ng/m(3) (±16, n = 3) for kerosene/charcoal mix, 334 ng/m(3) (±57, n = 3) for charcoal alone, and 5040 ng/m(3) (±909, n = 3) for open wood fires. Benzo[a]pyrene equivalent exposures for US EPA's priority PAH pollutants were 0 for LPG, 8 ng/m(3) for kerosene/charcoal mix, 44 ng/m(3) for charcoal, and 767 ng/m(3) for open wood fire. Inhalable pollutants are present at unacceptably high levels, exceeding indoor air quality standards for all but LPG fuels. Relative results provide an exposure profile for rural East Africa and support the feasibility of conducting a larger scale smoke exposure campaign in the region. The use of "fuel efficient" wood stoves for the reduction of PM(2.5) and PAH exposure was measured in a local secondary school. Proper use of "fuel efficient" wood stoves reduced personal and indoor exposure to measured pollutants by more than 90%, supporting further investigation into the applicability of this technology to significantly improve indoor air quality.

Characterization and Determination of PM2.5 Bound Polycyclic Aromatic Hydrocarbons (PAHS) in Indoor and Outdoor Air in Western Sierra Leone

“…The concentrations of PAH was highest in the kitchen than in outdoor and living room, respectively, and this observation could not be considered weird taking into account the cooking activities (source strength) and the type of biomass fuels that are used in kitchens where no proper ventilation system exists. Individual PAH concentration in kitchens with wood stoves are significantly elevated than those using charcoal by over an order of magnitude, suggesting further that wood stoves or wood burning devices are big emitter of PAHs, firmly consistent with previous studies [22,27,32]. Studies have shown that PAHs are highest in a similar environment where an indoor source (cooking or space heating or environmental tobacco smoke) dominate [33,34].…”

“…But the toxicity estimate measured by the BaPeq concentrations in this study in all of the three locations is not negligible since the threshold of 1 ng/ m 3 suggested by WHO for inhaled air was exceeded. The mean BaPeq concentration in the current study is lower than two previous studies conducted during cooking in kitchens with wood and charcoal stoves in Sierra Leone; 616 ng/m 3 and 58 ng/m 3 [27]; and in Tanzania; 391 ng/ m 3 and 92 ng/m 3 [32] but higher than the levels reported for children's exposure in outdoor air in New York 0.45 ng/m 3 [43].…”

“…Studies have shown that PAHs are highest in a similar environment where an indoor source (cooking or space heating or environmental tobacco smoke) dominate [33,34]. The level of PM 2.5 bound ∑ 11 PAHs observed in this study is lower in the kitchen environment than previous studies [22,24,27,32], but higher than the ambient levels measured in Europe and America [33,35]; even though the number of investigated PAHs vary. Different factors, such as ventilation rate, kitchen type and space, measurement duration, measurement activity etc.…”

Public health and components of particulate matter: The changing assessment of black carbon

“…A study from the highlands of Tanzania examined PM 2.5 and PAH concentrations in households burning different fuels for cooking (Titcombe and Simcik, 2011). The fuels used were liquefied petroleum gas (LPG), a kerosene/charcoal mix, charcoal, and wood (open burning).…”

Evaluation of Inhalation Exposure to Carcinogenic PM10-Bound PAHs of People at Night Markets of an Urban Area in a Metropolis in Eastern China

“…Therefore, fewer PAH emissions are expected when grilling foods with liquefied petroleum gas as fuel compared with charcoal as fuel. Furthermore, liquefied petroleum gas combustion during cooking causes lower concentrations of ambient PAHs than does charcoal consumption (Titcombe and Simcik, 2011). However, the PM 10 -bound PAH concentrations in the barbecue night markets in Hefei City were 1-2 orders of magnitude higher than those detected in urban areas (Mantis et al, 2005;Hong et al, 2007;Vu et al, 2011;Limu et al, 2013;Wu et al, 2014a), indicating that staff and consumers in barbecue night markets are significantly exposed to carcinogenic PAHs.…”