Vapor‐Phase and Particulate‐Associated Pesticides and PCB Concentrations in Eastern North Dakota Air Samples

Abstract

Vapor‐phase and suspended particulate (<50 µm) samples were collected on polyurethane foam (PUF) and quartz fiber filters in rural North Dakota to determine the air concentrations of pesticides in an area where agriculture is a primary source of semivolatile pollutants. Samples were collected at two sites from 1992 to 1994 that were at least 0.4 km from the nearest farmed fields and known application of pesticides, and analyzed for 22 different organochlorine, triazine, and acid herbicide pesticides. Fourteen pesticides were found above the detection limits (typically <1 pg/m3). The most prevalent species found in the PUF extracts were endosulfan I and II (6,7,8,9,10,10‐hexachloro‐1,5,5a,6,9,9a‐hexahydro‐6,9‐methano‐2,4,3‐benzodioxathiepin 3‐oxide, exo‐ and endo‐isomers, respectively) at <1 to 2200 pg/m3 and <1 to 500 pg/m3, respectively, trifluralin (2,6‐dinitro‐N,N‐dipropyl‐4‐trifluoromethylaniline) at 3 to 700 pg/m3, and 4,4′‐DDE (1,1‐dichloro‐2,2‐bis‐(4‐(chlorophenyl)ethylene) at 6 to 200 pg/m3. The most prevalent pesticides in filter extracts included carbofuran (2,3‐dihydro‐2,2‐dimethyl‐7‐benzofuranyl methylcarbamate) at <0.5 to 470 pg/m3, atrazine (2‐chloro‐4‐ethylamino‐6‐isopropylamino‐l,3,5‐triazine) at <0.4 to 46 pg/m3, 2,4‐D ((2,4‐dichlorophenoxy)acetic acid) at <0.4 to 1800 pg/m3, and chlorothalonil (2,4,5,6‐tetrachloro‐1,3‐benzenedicarbonitrile) at <13 to 7800 pg/m3. Concentrations of polychlorinated biphenyl (PCB) congeners were much lower (<50 pg/m3 in all cases) than many of the pesticides. These results demonstrate that pesticides are among the most prevalent chlorinated semivolatile pollutants present in rural North Dakota, that significant transport of pesticides occurs both in the vapor‐phase and on suspended particulate matter, and that blown soil may be a significant mechanism for introducing pesticides into surface and ground waters.

Diffuse geographic distribution of herbicides in northern prairie wetlands

“…Chem. 20,2001 277 bicides may also be related to their persistence in aquatic environments. Triallate may have a half-life in northern aquatic environments that exceeds a year [15].…”

“…Development of these largescale atmospheric events may be an important mechanism for accumulation of a relatively homogeneous mixture of volatile herbicides in the atmosphere. Once herbicides are in the atmosphere, they may sorb to airborne soil particles [19,20] and moisture in local convective clouds. Then the herbicides can be redeposited on the landscape in rain (Table 5).…”

Variations in environmental contamination by polychlorinated biphenyls (PCB) and chlorinated pesticides (Lindane, DDT) on ping farms in Hodonín district in 1994 to 1999

“…DDT is known to persist in soil for more than 30 years (Aislabie et al, 1997). A part of it is degraded by biological processes and another part volatilises (Hawthorne et al, 1996).…”

Uncertainties in the Current Knowledge of Some Atmospheric Trace Gases Associated with U.S. Agriculture: A Review

“…35 In North Dakota, a broad spectrum of organochlorines, triazine, and herbicides were found in regional air. 36 The relative absence of PCBs indicated that agriculture dominated the atmospheric SVOC. Aircraft measurements using relaxed eddy accumulation (REA) over agricultural and forested surfaces in Ontario found fluxes of atrazine from Ϫ1.1 to ϩ2.5 ng ⅐ m Ϫ2 ⅐ sec Ϫ1 and of metolachlor of Ϫ0.02 to ϩ0.56 ng ⅐ m Ϫ2 ⅐ sec Ϫ1 (negative away from the ground surface).…”