Residue airborne

An active pharmaceutical ingredient (API) batch fails to conform to established specifications and yet the manufacturer distributed it anyway. Deliberately blending API batches to dilute or hide noxious contaminant or filth or failing to determine actual yield and percentages of expected yields. Contamination of drugs with toxic chemicals, drug residues, airborne contaminants, or filth. 

Once all materials have been placed in the cabinet, allow the cabinet to operate for about three more minutes before commencing work in order to purge the cabinet of any residual airborne contamination. The worker should avoid interruptions after work in the cabinet has commenced. Be sure that laboratory doors are kept closed to avoid disruptive drafts. 

Monitoring the residual airborne effluent and controlling the dissolution to remain below the release specifications. 

Barium metal and most barium compounds are highly poisonous. A notable exception is barium sulfate which is nontoxic because of its extreme iasolubihty ia water. Barium ion acts as a muscle stimulant and can cause death through ventricular fibrillation of the heart. Therefore, care must be taken to avoid contact with open areas of the skin. Workers must wear respirators (of type approved for toxic airborne particles), goggles, gloves, and protective clothing at all times. The toxic barium aluminate residue obtained from barium production is detoxified by reaction with a solution of ferrous sulfate and converted iato nontoxic barium sulfate. According to OSHA standards, the TWA value for Ba and Ba compounds ia air is 0.5 mg/m. ... 

Sb and Ba are present in the airborne gunshot residue expelled from all of the brands of 0.22 cal ammo. A chemical analysis of the primer. of the Western brand gave a Ba to Sb ratio of 65, whereas the same ratio obtained from the data in Table 11 is 2.6. The authors conjecture that this additional Sb left in the air came from the vaporized bullet Pb which contains a large amt of Sb as a hardening agent... 

Fig 10 shows the variation of airborne gunshot residue collected at various times after one firing. Following a general initial exponential fall-off, the rate of decrease slows at 48 hrs after firing. 

Firing tests conducted with larger than 0.22 cal ammo showed that even greater sensitivity for detection of Ba and Sb in airborne gunshot residues... 

Majewski MS, Foreman WT, Goolsby DA, et al. 1998. Airborne pesticide residues along the Mississippi. Environ Sci Technol 32 3689-3698. 

Seiber JN, McChesney MM, Woodrow JE. 1989. Airborne residues resulting from use of methyl parathion, molinate and thiobencarb on rice in the Sacramento Valley, California. Environ Toxicol Chem 8 577-588. 

J.N. Seiber and J.E. Woodrow, Airborne residues and human exposure, in Determination and Assessment of Pesticide Exposure, ed. M. Siewierski, Studies in Environmental Science 24, Elsevier, New York, pp. 133-146 (1984). 

Farm worker exposure to pesticides has been studied extensively over the past 30 years.This scientitic discipline has evolved from the days when respiratory exposure of farm workers was measured using gauze dosimeters placed inside respirators to collect airborne pesticide residues to very sophisticated air sampling devices and remarkable dosimeter devices to measure dermal exposure to farm workers. ... 

The TDX values were much lower than the TUDX values, indicating that the protective clothing provides a substantial reduction in the amount of residues reaching the skin of the operator. The same operators who had higher overall exposure had higher actual exposure. The frequent occurrence of nondetectable residues is notable and indicates that some operators were able to keep exposure to levels at or near the limit of detection. The low respiratory exposure (REX) confirms the validity of the assumption that airborne exposure would be a minor route of exposure. (See Table 3.)... 

Popendorf, W.J., Spear, R.C., and Selvin, S. (1975) Collecting foliar pesticides residues related to potential airborne exposure to workers, Environ. Sci. Techno., 9 583-585. 

It can be seen from this figure that whether a round track or a wedge-shaped track is produced is related to the incidence angle and the residual range of the a -ray at the incidence point on the surface of detector. It can be shown that for the tracks produced by the deposited Po-218 and Po-214, the ratios of the round track density and the wedge-shaped track density to the total track density are 0.60 and 0.40, respectively. If the respective ratios for airborne activities are denoted as a and b, the round track density (Tr) and the wedge-shaped track density (T ) are represented by... 

Seiber JN, Woodrow JE. 1984. Airborne residues and human exposure. Studies in Environmental Science 24 133-146. 

Wesley and Wall (19) collected and analyzed airborne dust samples collected from three areas within five Mississippi gins in 1975. The general composition of their samples are summarized in Table IV. These data show the dust to be about 30 percent cellulosic, the remainder being soil and other materials. The quantitative elemental analysis of their samples is detailed in Table V. Although the percentages are different, the constituents in these samples of gin dust are very similar to those listed by Brown (18) in whole plant parts. None of the data presented have identified residues from insecticides or harvest aid chemicals. This may be because they were not specifically sought. 

Gas chromatography coupled to tandem mass spectrometry (GC-MS/MS [49]) prior to analysis of the three primary active components of cannabis (THC, cannabidiol and cannabinol) by this technique, airborne particulates were extracted in an ultrasonic bath with chloroform. The extracts were combined and concentrated under a stream of nitrogen. The residue was filtered through pre-washed disposable PTFE membranes, dried and finally reconstituted with cyclohexane. After separation and solvent partitioning, the extracts were analysed by GC-MS/MS. 

A convenient method is the spectrometric determination of Li in aqueous solution by atomic absorption spectrometry (AAS), using an acetylene flame—the most common technique for this analyte. The instrument has an emission lamp containing Li, and one of the spectral lines of the emission spectrum is chosen, according to the concentration of the sample, as shown in Table 2. The solution is fed by a nebuhzer into the flame and the absorption caused by the Li atoms in the sample is recorded and converted to a concentration aided by a calibration standard. Possible interference can be expected from alkali metal atoms, for example, airborne trace impurities, that ionize in the flame. These effects are canceled by adding 2000 mg of K per hter of sample matrix. The method covers a wide range of concentrations, from trace analysis at about 20 xg L to brines at about 32 g L as summarized in Table 2. Organic samples have to be mineralized and the inorganic residue dissolved in water. The AAS method for determination of Li in biomedical applications has been reviewed . 

Decontamination of JACADS will require chemical, mechanical, and thermal processing. The removal of critical structural components and systems from buildings will have to be planned to ensure structural stability. Residuals of any of the agents processed at JACADS (HD, GB, and VX) may be exposed during disassembly activities. These residuals will be harmful to anyone in the immediate area If they are vaporized, airborne agent concentrations could be harmful, so decontamination procedures for equipment, waste streams, and building materials must ensure that agent residues are destroyed, and the destruction must be verified. 

Particle size of insecticidal sprays has a bearing on the ability of airborne sprays to be transported and deposited, on foliage injury, and on the efficiency of residues in killing insects. Each problem should be carefully analyzed for the particle-size requirements. 

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