Occurrence of Pesticides and Herbicides in Soil and Sand Dust from Riyadh City, Kingdom of Saudi Arabia PDF

Keywords

Pesticides, Herbicides, Organic contents, GC-MS, Chlor-n-alkanes, Plasticizers, n- Alkanes, UCM

Abstract

Soil and sand dust resuspension is one of the major input mechanisms of harmful anthropogenic substances into the atmosphere of arid regions. Pesticides and herbicides are the major components of these toxic substances in soils of agricultural regions. This research examines the occurrence of pesticides and herbicides in soil and sand dust from various locations in the city of Riyadh, Kingdom of Saudi Arabia. The organic components, including pesticides, herbicides, fossil fuel residues, and natural lipids were analyzed by GC-MS for this area to define their sources and strengths. The results show that various pesticides and herbicides are present in soil and sand dust in Riyadh City and include Carbofuran, Chlorpyrifos, Oxadiazon, Ethoprophos, Dimpylate, Iso-Octyl-MCPA, Methyl dichloro fop, Endosulfan I and II, and other unknown derivatives. Anticorrosive reagents such as 1-chlorododecane and 1- chlorotetradecane and plasticizers are also significant compounds in these samples. The occurrence of pesticide and herbicide residues in most of the samples from the city is due to activities related to agriculture. Local agriculture and gardening applications of these pesticides are suggested to be the main sources of these compounds in soil and sand dust of the city. The presence of chloro-n-alkanes is attributed to contamination from anti abrasion-antiwear lubricating oils used for protecting petroleum production equipment. The occurrence of plasticizers in these samples is attributed to tyre and plastics abrasion products. n-Alkanes, UCM and series of hopane and sterane biomarkers were also detected in these samples. The n-alkanes, ranging from C1 to C36 maximum abundances at various carbon numbers, hopane biomarkers and UCMS support the input of particles from vehicle emissions and the excess n-alkanes with odd carbon number preferences, as well as methyl n-alkanoates indicate natural vegetation sources.