Working lindane

Wilson and co-workers [332, 333] have discussed the determination of aldrin, chlordane, dieldrin, endrin, lindane, o,p and p,p isomers of DDT and its metabolites, mirex, and toxaphene in seawater and molluscs. The US environmental Protection Agency has also published methods for organochlo-rine pesticides in water and wastewater. The Food and Drug Administration (USA) [334] has conducted a collaborative study of a method for multiple organochlorine insecticides in fish. Earlier work by Wilson et al. [333, 335] in 1968 indicated that organochlorine pesticides were not stable in seawater. 

Cyclodiene pesticides, of which endrin and its oxidized analogs are representative, can also be estimated by receptor-assay technique. Cyclodiene pesticides exert their mode of action by altering central nervous system membrane ion transport. In work reported by Saleh et al. (1993), a labeled amino acid, GABA, that binds to the chloride channel receptor is displaced by endrin (and other similar molecules), and thus serves as an assay for these pesticides. The GABA receptor was shown to be a potentially useful biomarker for organochlorine pesticides such as lindane, toxaphene, endrin, chlordane, and others. The assay involves small quantities of blood (0.1 mL), and requires only that the plasma be separated from the... 

I would call myself an environmentalist, but there are different lands. I am not strict. If I had an outbreak of bugs that were going to kill the trees I ve worked on for twenty years, there would be no question that I would spray to get rid of them. I would use lindane, even though it s illegal, because I have worked on those trees for decades. But I try to keep from doing any more spraying than I have to. 

Irrmost correlations in this review, the steric parameters are supposed to be best among others. In deriving Eq. 43 for N-phenyl tetrahydrophthalimide herbicides, STERIMOL parameters are the best ones 42). In Eq. 53 for lindane analogs, Vw works much better than MR 70). However, this does not necessarily mean that the correlations mentioned here are always finalized. Further improvement may be possible using other steric parameters. 

Lindane (Kwell, etc) is available as a shampoo or lotion. For pediculosis capitis or pubis, one application of 30 mL of shampoo is worked into a lather and left on the scalp or genital area for 5 minutes and then rinsed off. No additional application is indicated unless living lice are present 1 week after treatment. Then reapplication may be required. Recent concerns about the toxicity of lindane have altered treatment guidelines for its use in scabies the current recommendation calls for a single application to the entire body from the neck down, left on for 8-12 hours, and then washed off. Patients should be retreated only if active mites can be demonstrated, and never within 1 week of initial treatment. 

ICI Scientists working on lindane received the news of the new Swiss insecticide, but not its structure, around Christmas time in 19 3 So similar were the reported insecticidal properties of DDT to those of lindane that there was speculation as to whether the two compounds were variants of the same chemical. 

At a given spray concentration and application rate, solutions are more reliable. Emulsions of lindane usually work well enough, however, if applied in larger volume or at higher concentration. Elimination of the oil carrier reduces the cost and also the hazard of phytotoxic reactions where living trees are sprayed for protection. Several early studies report the excellent control afforded by lindane emulsions (4, 5,12,14, 20, 23), and reports on the excellent performance of lindane emulsions on a wide assortment of bark beetle species have recently grown (6, 7, 8, 9, 10, 17, 37, 40, 44). Massey (28) has reported on the successful use of an emulsion of DDT to protect living trees. 

Case study and worked example — Calculating water concentrations of Lindane... 

Since peaks not identifiable as phenoxy herbicides appeared in many of the samples, qualitative standards of systox, malathion, DDT, aldrin, lindane, BHC, and chlordan were chromatographed to establish approximate retention times for these insecticides in our columns. While it was beyond the scope of this work, quantitative detection of insecticides in these samples appeared feasible. 

Average serum concentrations of 0.07, 0.19 and 0.04 ig/ml of a-benzene hexachloride (a-BHC), J5-BHC and y-BHC, respectively, were reported in 57 subjects who worked in a factory manufacturing lindane fi-BHC was the only isomer observed to accumulate on chronic exposure. A mean fat concentration of 45.6 pg/g of )9-BHC was reported in 8 subjects (K. Baumann et al., Int. Archs occup. envir. Hlth, 1980, 47, 119-127). 

Chromatograms of pesticides obtained by Wilmott and Dolphin monitored with a standard UV absorption detector and the electron capture detector are shown in figure 14. It is seen that 3.2 x 10 g of lindane is clearly detected by the electron capture detector whereas it is not discernible on the trace from the UV detector. However, for the system to work the solutes must be relatively volatile and, as already discussed, the mixture would probably be better separated and analyzed employing a GC technique. 

Despite the relatively uniform in vivo impacts of this group of compounds, there is a suggestion from the work by Betoulle et al.13 that at least one OC pesticide, lindane, may have biphasic effects on fish macrophages. At low concentrations (2.5-25 pM), in vitro exposure to lindane stimulated ROS production by Ca2+-independent... 

Sorption phenomena are well described and documented in the basic scientific hterature [1] and standard physical chemistry texts [2-4]. Indoor air researchers first reported extensively on adsorption to and desorption from indoor surfaces in 1987 at the 4th International Conference on Indoor Air Quahty and Climate in Berlin where Seifert and Schmal [5] reported the sink effects of plywood and carpet exposed to lindane and a mixture of 20 volatile organic compounds (VOCs). The Berlin conference also provided data from two studies that examined the sink effect of textiles [6,7]. Finally, Skov and Valbjorn [8] reported on the seminal Danish town hall study. They concluded that sorption to and from large surface areas and fleecy materials was associated with lAQ problems. This work was followed up by Nielsen [9] at Healthy Buildings 88 in Stockholm, where he reviewed several studies on the importance of sorption processes on lAQ. Also in Stockholm, Berglund and her colleagues [10] provided an extensive hterature review and discussion of lAQ data leading to the conclusion that sink effects are important. They also provided the results of a study on adsorption and desorption in a ventilation system. Since then, numerous overviews have been presented on the importance of sink effects on lAQ [11,12]. 

One important group of insecticides, the avermectins, works differently by being agonists and not antagonists as the other, acting on the chloride channels. The avermectins are produced by Streptomyces avermitilies. The binding site is different, and cross-resistance to fipronil, the cyclodienes, and lindane does not seem to occur. The toxic symptoms in insects and mammals are different. Mammals poisoned with avermectins exhibit hyperexcitability, incoordination, and tremor followed by ataxia and paralysis. In insects and nematodes, the hyperexcitation phase is absent. Their symptoms are... 

By restricting this article to FP calculations, we exclude the large body of ab initio computational work based on the cluster as a surface model. Other reviews compare both proaches [2]. We likewise do not consider semi-empirical methodologies or pair-potential methods. A very recent comprehensive look at FP calculations in theory and in practice is that of Lindan et al. [6]. Equally, Ref. [7] is a review aimed somewhat at the geological community, discussing atomistic and ab initio methods for modelling minerals. 

This review summarizes some of the proposed products and pathways of the anaerobic degradation of the chlorinated hydrocarbon pesticides. Some aerobic work is included because the organisms studied existed anaerobically in the environment. The most work has been conducted with DDT and related compounds. There is some information on dieldrin with less on endrin and lindane. The other chlorinated hydrocarbons have received little attention. 

A study in 26 men occupationally exposed to a mixture of insecticides, predominantly DDT, chlordane and lindane, found that the half-life of phenazone 10 or 15 mg/kg was reduced from 13.1 hours, in a group of 33 unexposed subjects, to 7.7 hours in the exposed group. The significance of this is unclear as changes in working practices have reduced occupational exposure to such chemicals. 

The plasma half-life of phenylbutazone in a group of men who regularly used chlorinated insecticide sprays (mainly lindane) as part of their work, was found to be 20% shorter (51 hours) than in a control group (64 hours), due, it is believed, to the enzyme-inducing effects of the pes-... 

This high and reproducible percent recovery for the isolation and recovery of lindane from water strongly suggests that RP-SPE is very appropriate as a sample preparation method for this analyte. Lindane is of continued interest to environmental and toxicological scientists. One such study, discussed next, taken from the author s work, involves the isolation and recovery of lindane from homogenized myometrial tissue suspended in an aqueous matrix. 

A series of calibration or working standards were prepared from the metha-nolic stock solution containing lindane. This stock solution was prepared by carefully weighing out pure solid lindane on an analytical balance. These standards were injected into the C-GC-ECD from lowest to highest lindane concentration. The peak at 1.8 min was identified as a reference peak in the Turbochrom software and a narrow window was defined around the t[i ] of the apex of the peak. A calibration curve was constructed using a least squares regression algorithm in the software. A correlation coefficient of 0.9990 was obtained. 

Retrieve the Turbo method titled LEMIS, which stands for lindane, endrin, methoxychlor, internal standard mode of calibration allow sufficient instrument equilibration time. Write a sequence encompassing the calibration standards, ICV, and unknowns. Save the sequence as a file with the name, for example, G 0317 (group, March 17th). Begin to inject a 1-pL aliquot of each working standard. Initially inject iso-octane, then inject in the order lowest to highest concentration level. This order is important because it prevents carryover from one standard to the next. 

Very often, metal oxide surfaces will reconstruct when exposed to water as was discussed for MgO. We will illustrate the importance of such a reconstruction by comparing the reactivity of the (001) surface of anatase (Ti02) with that of the rutile (110) surface of Ti02- Both are the siufaces of lowest energy for the respective phases. The difference between anatase and rutile relates to the stacking of the TiOe octahedra in both phases. In anatase, the octahedra stack tetrahedrally, whereas in rutile they stack parallel. Quantum-chemical results are available for both phases as well as for their corresponding surfaces. We refer here to the work of Arrouvel et al. on the (100) siuface of Ti02 anatase and of Lindan et al. on the (110) siuface of rutile. The respective surfaces are shown in Fig. 5.4a and b. 

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