Contents and sources of polycyclic aromatic hydrocarbons and organochlorine pesticides in vegetable soils of Guangzhou, China.
We investigated contents, distribution and possible sources of PAHs and organochlorine pesticides (Ops) in 43 surface and subsurface soils around the urban Guangzhou where variable kinds of vegetables are grown. The results indicate that the contents of PAHs (16 US EPA priority PAHs) range from 42 to 3077 microg/kg and the pollution extent is classified as a moderate level in comparison with other investigations and soil quality standards. The ratios of methylphenanthrenes to phenanthrene(MP/P), anthracene to anthracene plus phenanthrene (An/178), benz[a]anthracene to benz[a]anthracene plus chrysene (BaA/228), indeno[1,2,3-cd]pyrene to indeno[1,2,3-cd]pyrene plus benzo[ghi]perylene (In/In+BP) suggest that the sources of PAHs in the soil samples are mixed with a dominant contribution from petroleum and combustion of fossil fuel. The correlation analysis shows that the PAHs contents are significantly related to total organic carbon contents (TOC) (R2=0.75) and black carbon contents (BC) (R2=0.62) in the soil samples. Dichlorodiphenyltrichloroethane and metabolites (DDTs) and hexachlorocyclohexanes and metabolites (HCHs) account largely for the contaminants of OPs. The concentrations of DDTs range from 3.58 to 831 microg/kg and the ratios for DDT/(DDD+DDE) are higher than 2 in some soil samples, suggesting that DDT contamination still exists and may be caused by its persistence in soils and/or impurity in the pesticide dicofol. The concentrations of HCHs are 0.19-42.3 microg/kg.
State Key Laboratory of Organic Geochemistry, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Wushan, Guangzhou, Guangdong 510640, China.
Laiguo
L
Chen
Yong
Y
Ran
Baoshan
B
Xing
Bixian
B
Mai
Jianghua
J
He
Xiuguo
X
Wei
Jiamo
J
Fu
Guoying
G
Sheng
D002244:Carbon / Q000032:analysis; D002681:China; D018556:Crops, Agricultural; D004784:Environmental Monitoring; D006843:Hydrocarbons, Chlorinated / Q000032:analysis*; D010575:Pesticides / Q000032:analysis*; D010578:Petroleum; D011084:Polycyclic Aromatic Hydrocarbons / Q000032:analysis*; D012989:Soil Pollutants / Q000032:analysis; D014675:Vegetables
D006843:Hydrocarbons, Chlorinated; D010575:Pesticides; D010578:Petroleum; D011084:Polycyclic Aromatic Hydrocarbons; D012989:Soil Pollutants; D002244:Carbon