[1] Cloud water, rainwater, and aerosol particles were collected in Puerto Rico from December 2004 to March 2007 in order to investigate their chemical composition, relation to sources, and removal processes. The species analyzed were inorganic ions, metals, total and dissolved organic carbon (TOC, DOC), total nitrogen (TN), and organic acids. For all samples, the dominant species were marine (Na⁺, Cl⁻), representing about 50%–65% of total content. Non‐sea‐salt fraction was dominated by SO₄²⁻ (17%–25%), followed by water‐soluble organic (2%–8%) and total nitrogen (2% –6%) compounds. Organic acids represented contributions to the organic fraction in cloud water of 20% and 6% for aerosol particles. Inorganic species were predominant in total nitrogen portion. The chemical composition of cloud water, rainwater, and aerosol particles were observed to be sensitive to transport patterns. Air masses from northwest Africa showed the highest concentrations of nss‐Ca²⁺, Fe, and Al, suggesting a crustal origin. The pH values for cloud water and rainwater observed under this transport pattern were higher than background conditions, probably due to the alkalinity associated with nss‐Ca²⁺. The highest concentrations of Cl⁻ and SO₄²⁻, with lower pH, were measured during periods of influence from Soufriere Hills volcano eruptions, most likely due to emitted SO₂ and HCl. Air masses from North America had an anthropogenic influence, where levels of nss‐SO₄²⁻, TOC, and TN were higher (∼4 times) than in clean air masses. These results suggest that long‐range transport could be an extra source of metals and organic/nitrogen species to the Caribbean region ecosystems.

Aerosol particle samples (PM10) were collected at urban, industrial and rural sites located in Rio de Janeiro, Brazil, between October 2008 and September 2009. Aerosol samples for each site were analyzed for total and soluble metals, water-soluble ions, carboxylic acids, and water-soluble organic carbon (WSOC). The results showed that the mean PM10 concentrations were 34 μg m⁻³; 47 μg m⁻³ and 71 μg m⁻³ at the rural, urban and industrial sites, respectively. An increase in the average concentration of these particles due to air stagnation was observed during the period from May to September for all sites, and an increase in hospitalization for respiratory problems was also reported. On average, the anions species represented 4 to 14% of total content, while cations species corresponded to 1 to 11% and 7.5% for WSOC. The overall metal content at the industrial site was nearly the double that at the rural site. The concentrations of the studied species are influenced mainly by site location and the specific characteristics present at each site. However, higher concentrations of some species were observed on particular dates and were probably due to biomass burning and African dust events. The acid/aqueous percentiles showed that the most efficiently extracted metals from the aqueous phase were V and Ni (40%), while Al and Fe represented a lower percentage (<3%). Analysis of the aqueous fraction provides important information about the bioavailability of metals that is associated with the inflammatory process in the lungs.

Resumo A poluição do ar em ambientes fechados é agravada pela queima de lenha em fogões rústicos e ambientes pouco ventilados. A exposição aos poluentes emitidos por este tipo de combustível resulta no aumento da morbidade e da mortalidade. No Brasil, os estudos e as estimativas são escassos. Visando entender esta problemática, o objetivo deste trabalho foi investigar o uso de lenha utilizando as séries de dados das agências governamentais para estimar o número de pessoas expostas. Os resultados apontam que a lenha é o segundo combustível mais usado para cozinhar, sendo utilizada por uma parcela significativa da população, em torno de 30 milhões de brasileiros. Um fator decisivo no maior uso deste combustível é o nível socioeconômico da população associada ao preço do gás liquefeito de petróleo (GLP). Os estudos realizados no país registraram concentrações altas de partículas durante a queima da lenha, excedendo os limites sugeridos pela Organização Mundial da Saúde (OMS). Também foram observadas associações entre a exposição aos poluentes gerados pela queima e o agravamento dos mais diversos problemas de saúde, dentre eles doenças respiratórias e câncer. A substituição da lenha e outros combustíveis sólidos por combustíveis mais limpos deve ser a meta do governo para minimizar custos com a saúde.