Concentración de pesticidas organoclorados en aire del sur de la cuenca del Plata: un año de muestreo
Polyurethane foam passive air samplers (n=21) were deployed across La Plata River south basin to assess the concentration and distribution of organochlorine pesticides (OCPs) for ≈ 3-5 months periods all over a year. Annual average concentration of OCPs ranged from 326 to 9000 pg.m-3 with predominan...
Guardado en:
| Autores principales: | , , , |
|---|---|
| Formato: | Articulo |
| Lenguaje: | Español |
| Publicado: |
2013
|
| Materias: | |
| Acceso en línea: | http://sedici.unlp.edu.ar/handle/10915/60701 |
| Aporte de: |
| Sumario: | Polyurethane foam passive air samplers (n=21) were deployed across La Plata River south basin to assess the concentration and distribution of organochlorine pesticides (OCPs) for ≈ 3-5 months periods all over a year. Annual average concentration of OCPs ranged from 326 to 9000 pg.m-3 with predominance of Σendosulfans (Endo). Annual averages of Endo (230-8936 pg.m-3) are higher than reported values for other countries in the Latin American region (Brazil, Bolivia, Chile y Colombia: 114- 898 pg.m-3). Maximum values correspond to the warm period in areas with intense soybean culture: North of Buenos Aires and South of Entre Ríos and Santa Fe (3072-21521 pg.m-3). Concentrations of DDTs (12-235 pg/m3) are an order of magnitude lower than sites where it is now used against malaria (India: 5356 pg.m-3; South of Mexico: 2360 pg.m-3) but DDT/DDE ratio (1.1 - 6.8) >1 suggests a relatively fresh contribution, possibly due to the use of dicofol that presents this compound as impurity. The HCHs showed a high concentration in Zárate (801-8348 pg.m-3) where they predominated (66% of the total) with an α/ γHCHs ratio ≈7 similar to the technical mixture. Meanwhile, concentrations from other sites were one order of magnitude lower (7-199 pg.m-3) and indicated fresh inputs.
In the Metropolitan area, chlordanes prevailed (83-691 pg.m-3) representing 5-45 % of the total, especially in Buenos Aires City where the cis/trans-chlordane relationship >> 1.6 indicates a fresh contribution. In conclusion, OCPs have different spatial distribution: higher concentrations in agricultural areas, diversity in composition and higher values of chlordanes in urban areas. Concentrations and relationship values suggest illegal inputs and/or long-range transport. |
|---|