Toxaphene recommendations

A sample of alfalfa hay from Bozeman, Mont., that had received two spray applications, each of 4 pounds of technical toxaphene per acre, was found by the method recommended by Carter and Hubanks (3) to contain 225 p.p.m. of organic chlorine, equivalent to 331 p.p.m. of toxaphene. This sample was obtained from a bale approximately 5 months after the last spray application. A similar sample of untreated hay was found to contain 1.2 p.p.m. of organic chlorine. 

Samples of abdominal fat from a steer that had been fed hay containing toxaphene residues and from a steer that had been fed untreated hay were analyzed for their organic-chlorine content by the method recommended by Carter (i). The organic-chlorine content of the fat from the treated steer in excess of the amount found in the untreated steer was equivalent to approximately 700 p.p.m. of toxaphene. 

In water, the concentration of toxaphene considered safe for protection of freshwater life is conservatively estimated to lie between 0.008 and 0.013 pg/L for marine life, it is 0.07 pg/L. This is in sharp contrast to the current recommended drinking water criterion for human health protection of 5.0 to 8.8 pg/L. Similarly, residues in fish tissue in excess of 0.4 to 0.6 mg/kg wet weight may be hazardous to fish health and should be considered as presumptive evidence of significant environmental contamination, although fish may contain up to 5.0 mg/kg before they are considered hazardous to human consumers. Toxaphene criteria for human health protection — which range in various foods from 0.1 mg/kg for sunflower seeds to 7.0 mg/kg in meat, fats, and citrus fruits — also appear adequate to safeguard sensitive species of wildlife. 

There has not been sufficient work done on the control of these bugs to justify the making of definite recommendations for their control. In a very small number of fields observed during the past season, dieldrin at 0.25 pound and toxaphene (chlorinated camphene) at 1.5 pounds, applied by airplane, reduced the number of bugs to the point that serious injury was averted. 

Although flooding has been recommended for the control of fall army worms in rice, in the writer s experience this method is not effective. Toxaphene applied as a spray at the rate of 2 pounds per acre has been found to constitute good control. 

The International Joint Commission of the United States and Canada recommend a water quality standard of 0.008 pg/L for the protection of freshwater aquatic life. This standard is based on the study by Mayer et al. (1975), who found that toxaphene at 0.039 pg/L in water caused a significant increase in mortality and a significant decrease in growth of surviving brook trout fry over a 90-day period. The standard of 0.008 pg/L is obtained by applying an uncertainty value of 5. 

These results have significant economic implications for commercial fishers and for aboriginal peoples in the region who depend on the fishery as a major food source. In the United States no consumption of fish with greater than 4.8 xg/g wet weight is recommended based on noncancer health endpoints or 0.18 xg/g (ww) based on cancer endpoints [160]. As of December 1998 there were six fish consumption advisories for toxaphene in the USA, but they were all for locations in the southern states [ 160]. No toxaphene advisories for Great Lakes fish consumption have been issued by the Great Lakes states. 

Fig. 1. Typical toxaphene product (here the East-German Melipax). This formulation was used against insects in fruit-growing and contained about 10% toxaphene. The recommended application amount was 20 g (i.e., 2 g toxaphene) per 10 m2. It was distributed in 500 g units at a price of about 1 /unit...

Electrophilic nitration of aromatic organochlorines with a 1 1 mixture of concentrated HN03 and H2S04 was recommended to eliminate interfering compounds [ 144]. Both methods have the disadvantage that PCBs are destroyed so that they have to be quantified before. Nitration was also suggested as an additional clean-up step after pre-separation of PCBs DDT and its metabolites are eliminated from the toxaphene fraction [137]. 

The search of the literature carried out for this survey, allows us to estimate that approximately 90% of all toxaphene separation were carried out on non-polar stationary phases similar to 95% methyl-/5% phenylpolysiloxane and commercially available under the trade names DB 5, CP-Sil 8, HP-5, Ultra 2, Rtx 8, SE 52, etc. Two reports in the literature suggest the use of non-polar only. Alder et al. mentioned the decomposition of B8-1413 (P-26) and B9-1025 (P-62) on the polar DX-4 phase [145]. Baycan-Keller and Oehme tested four different stationary phases (capillary length 12 to 30 m) and found a remarkable decomposition of labile toxaphene compounds on 90% dicyanopropyl-/10% phenylcyanopropyl-polysiloxane (Rtx-2330) [146]. Therefore, the exclusive use of non-polar stationary phases was recommended for the quantification of toxaphene as well as a second column for confirmation of the results. A very non-polar stationary phase (CP-Sil 2) was suggested for the congener-specific separation of toxaphene [147,148]. 

The Environmental Protection Agency has established a limit of 0.003 mg 1 of drinking water and also requires that spills in excess of 1 lb be reported. The Occupational Safety and Health Administration (OSHA) has established a permissible exposure limit of 0.5 mg toxaphene per m for an 8 h day/40 h work week. The National Institute for Occupational Safety and Health recommends that toxaphene levels should at the lowest dose/concentration as possible in the workplace due to the potential for toxaphene to be carcinogenic in humans. The American Conference of Governmental Industrial Hygienists recommends a limit equal to that established by OSHA and that lmgm should not be exceeded over a 15 min period. 

SPILL CLEAN-UP Sweep spilled substance into sealable containers use wet vacuuming or moisten first to prevent dusting activated carbon and polyolefin or polyisobutylene fibers are recommended for use in the cleanup of mixtures including toxaphene. 

From the massive rejection of the chlorinated cyclodienes, two survivors emerge, both recommended by IPM (p. 244). The first of these is endosulfan 6,48) with inbuilt biodegradability. The second is campheclor (formerly called toxaphene) said to be a mixture of about 175 polychloro derivatives of cam-phene 6.49) with an overall empirical formula ofCioHjoClg, and no double bond (Casida et al., 1974). It, too, is biodegradable. 

The chlorinated compounds should be completely separated in the order listed in Section 2, with heptachlor nearest the solvent front and dicofol closest to the origin. Other common organochlorine insecticides that can be detected and identified by this TLC procedure include aldrin, DDE, DDT, TDE (DDD), endrin, BHC, daconil, methoxychlor, captan, toxaphene, and chlordane. Alternative mobile phases that should be tested for any particular mixture not separated by hexane-acetone (99 1) include hexane (recommended for aldrin, heptachlor, p,p -DDE, o,p and p,p -DDT and p,p -TDE) benzene-hexane (1 1) and hexane-methanol (99 1) (applicable to more polar pesticides). 

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