Occurrence and vapor particle partitioning of heavy organic compounds in ambient air in Brazzaville, Congo

Abstract
High volume air samples for organochlorine (OC) pesticides, polychlorinated biphenyls (PCB) and polycyclic aromatic hydrocarbons (PAH) were collected during August–September 1989 in Brazzaville, Congo (4·14°S, 15·14°E). Average concentrations (ng/m3) were ΣDDT = 2·8; ΣHCH (hexachlorocyclohexane) 0·42; Σchlordane = 0.027; ΣPCB = 0.55; Σ3–6 ring PAH = 42; total DDT concentrations in Brazzaville fell between those reported in Porto Novo and Delhi (India) and were 20–100 times higher than those found in US cities. The average γ-HCH to α-HCH ratio (11) indicated use of lindane instead of technical HCH. The similarities between chlordane levels in Brazzaville and the open ocean indicated that little or no local use occurs. PAH levels were about equal to or lower than those reported in US cities, whereas PCB levels were three times lower. Vapor/particle distribution coefficients for several OC and PAH were in good correlation with their vapor pressures. The fraction of PAH on particles was greater than that of OC pesticides.