Are Mexican Agricultural Farmlands PCDD/F Soil Reservoirs?

Abstract

Our aim was to identify polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzo-p-furans (PCDFs) in agricultural farmland soils in the Northwest of Mexico. We obtained ≈50 g of soil in five Yaqui Valley (VY) agricultural fields in the north-western Mexican State of Sonora and in five Culiacán Valley (VC) agricultural fields in the north-western Mexican State of Sinaloa. Fields with minimal tillage, with ferti-irrigation, and those with intensive aerial and manual tillage were included. All soil samples were subjected to the chemical activated luciferase gene expression (CALUX(®)) test to determine PCDD/F. On average, samples contained 4.2 ± 1.2 PCDD/F ppt TEQ; VY soil samples contained 4.72 ± 1.23 PCDD/F ppt TEQ, while VC soil samples showed 3.6 ± 1.1 PCDD/F ppt TEQ (p = 0.47). On considering tillage-type, in agricultural fields catalogued as intensive tillage, PCDD/F concentrations were 4.40 ± 0.43 in agricultural fields catalogued as intensive tillage, while in farmlands of another tillage-type these concentrations were slightly higher (5.53 ± 0.8).

Combination of a Fast Cleanup Procedure and a DR-CALUX® Bioassay for Dioxin Surveillance in Taiwanese Soils

“…With regard to the use of AhR reporter gene bioassays to investigate dioxin-contaminated soils, the mean value in the present study was higher than those from the other studies [8,28,29]. Dioxin contamination levels in eastern Taiwan ranged from 1.3 to 45.6 pg BEQ/g d.w. (mean = 7.8 pg-BEQ/g d.w., SD = 5.08 pg-BEQ/g d.w.), and thus were slightly higher than those in farmland soil near villages located in northwestern Mexico (4.2 pg-BEQ/g d.w) [28] and soil near the Bohai Sea in China (3.8 pg-BEQ/g d.w.) [29].…”

“…With regard to the use of AhR reporter gene bioassays to investigate dioxin-contaminated soils, the mean value in the present study was higher than those from the other studies [8,28,29]. Dioxin contamination levels in eastern Taiwan ranged from 1.3 to 45.6 pg BEQ/g d.w. (mean = 7.8 pg-BEQ/g d.w., SD = 5.08 pg-BEQ/g d.w.), and thus were slightly higher than those in farmland soil near villages located in northwestern Mexico (4.2 pg-BEQ/g d.w) [28] and soil near the Bohai Sea in China (3.8 pg-BEQ/g d.w.) [29]. Our values for the soil from eastern Taiwan were comparable to those for soils around waste incineration plants located at Zhejiang province in southeastern China (11.0 pg-BEQ/g) [8], and soil near the Yellow Sea on the western coast of South Korea (9.2 pg BEQ/g d.w.) [29].…”

“…Many environmental scientists have examined soils near stationary points with high dioxin emissions [10,13,20,21]. Recently, several studies have carried out soil dioxin surveys in various local regions [22,23,24], but only a few studies have used bioassays to determine soil dioxin levels [8,25,26,27,28,29]. A high correlation has been found between dioxin levels measured using the in vitro aryl-hydrocarbon-receptor (AhR) reporter gene assay and dioxin levels measured using chemical assays [8,30,31].…”

Use of a highly sensitive recombinant hepatoma cell method to determine dioxin concentrations in samples of fish and crab from a hotspot area

“…Processes & Impacts PAPER (TEQ) in various samples including sh. [10][11][12][13][14][15] Compared with the HRGC/HRMS analysis, the DRE-CALUX bioassay is more costeffective and less time-consuming. New strategies have improved the precision and sensitivity of in vitro aryl hydrocarbon receptor (AhR) reporter gene assays.…”