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demonstrated in model systems that significant amounts of acrylamide are formed by the high- temperature reaction of glucose and the common amino acid asparagine. Since potato products are especially high in asparagines, it is now thought that this Maillard reaction is most likely responsible for the majority of the acrylamide found in potato chips and French fries (12). Acrylamide in the environment has high mobility in soil (24). [t may travel great distances in groundwater (10) and is biodegradable in water and soil (8; 13). It is not absorbed significantly by sediments or affected by conventional water treatment (7). Acrylamide is biodegradable and does not accumulate in soils. At ambient temperatures, half-lives range from 18 to 45 hours for 25 ppm acrylamide (25 mg AMD/kg soil) (24). Decreasing the temperature or increasing the acrylamide concentration increases half life. The half life was found to be longer under anaerobic soil conditions (24). Acrylamide is hydrolyzed in soils producing ammonium ions (NH4) that are eventually oxidized to nitrite (NOZ) and nitrate (N03) under aerobic conditions (1). Croll et al. (13) has shown acrylamide to be biodegradable in the laboratory and in effluent in which PAM was used as a flocculent. Brown et al. (7) reported acrylamide to be biodegradable in all unsterilized natural and polluted waters. Degradation of acrylamide usually occurs within 100 to 700 hours in water under aerobic conditions. Materials and Methods Experiment 1: Disappearance of TPH in Open Soil Microcosms Khaitan et al. (22) investigated the disappearance of TPH from open soil microcosms. The soil was taken from Department of Agronomy, Kansas State University. The soil contained 24% sand, 50% silt, 26% clay, 0.086% N, 0.95% C, and 1.4% organic matter (Soil Testing Lab, Dept. of Agronomy, Kansas State Univ.). Soil was ground, sieved and dried for 24 hours. Superfloc (solid crystal PAM) and Cydril (a mixture of PAM and TPH) were obtained from Cytec industries for the experimental work. Three replicates were made in open containers (four 120 ml bottles) with a mixture which contained 8.0 g of water, 0.27 g Cydril and 0.13 g Superfloc added to 20 g soil in each container. Extraction was performed at regular time intervals of t= 0, 2, 4 weeks. The whole bottle was taken for extraction at each time. After 60 ml of acetone was added for each extraction, the TPH was allowed to separate by shaking for approximately 2 hours so that hydrocarbon phase from soil moves into the acetone. After that, centrifuging at 500 rpm was done for 10 minutes. An empty (60 ml) bottle was taken and weighed with cap. Extract was poured into the bottle and whole bottle was weighed with cap. The difference of the final and initial weight gave the mass of extract in the bottle. The extract was subsampled with a plastic syringe capped with a filter. Finally, the filtered extract was transferred to a GC vial and capped tightly using a capper. The amount of TPH was determined using a HP GC 5890 Series II with Flame Ionization Detector (FID). Column specifications are 0.32 mm inside diameter, 30 m long, 0.00025 mm film thickness. The carrier gas was hydrogen; make-up gas was nitrogen and fuel gas was hydrogen and air. The temperature program was 40°C for 2 min followed by 10°C increase/min to 300°C. The detector temperature was 300°C while injector temperature was 200°C. Injection was set at 2 microliters per run and the vials were placed on an automatic sampler for analysis. 4