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Inhalation Toxicity of Metal Particles and Vapors
Published in Jacob Loke, Pathophysiology and Treatment of Inhalation Injuries, 2020
The threshold limit value as a time-weighted average in workroom air for an 8 hr day is 0.5 mg/m3 for antimony and compounds and Sb2O3. Although no exposure is recommended in Sb2 O3 production based on its carcinogenic potential in humans. The TLV for stibine (SbH3), the volatile hydride, is also 0.5 mg/m3. Its short-term exposure limit is 1.5 m/m3 (ACGIH, 1983). Stibine gas exposure is a serious exposure risk when lead-acid storage batteries are charged in a closed area. The OSHA permissible limit for antimony and compounds is 0.5 Sb/m3 (OSHA, 1981).
Exposure Assessment
Published in Ted W. Simon, Environmental Risk Assessment, 2019
The United States Occupational Safety and Health Administration (OSHA) has used this type of time-weighting since the 1970s. OSHA usually provides several regulatory values that are specific to different time periods. The permissible exposure limit is generally compared with an 8-hour time-weighted average to represent a work day. The short-term exposure limit is developed to provide safety for a 15-minute exposure.
Risk Assessment in Practice and Setting Exposure Limits
Published in David Woolley, Adam Woolley, Practical Toxicology, 2017
Those that cover the workplace generally assume intermittent exposure, usually for no longer than a typical working day of 8 hours in a 40-hour week, and can set average exposure limits [time-weighted averages (TWAs)] or maximum concentrations that are tolerable transiently within the working day, usually for no longer than 15 minutes [threshold limit value–ceiling (TLVC), short-term exposure limit (STEL)]. The occupational exposure band, as distinct from the OEL, places compounds into four or five bands of acceptable concentrations based on their known or expected toxicity. They are used when there is little information about the chemical, particularly for human effects. A further concept increasingly used in risk assessment is the TTC, which is used in assessment of chemicals in food and, increasingly, in areas such as genotoxic impurities in pharmaceutical drug substances.
Exploring research gaps and trends in the management of acute phosphide poisoning: a systematic review
Published in Critical Reviews in Toxicology, 2023
Zahraa Khalifa Sobh, Marwa Kholief, Eman Khalifa Sobh, Manal Ibrahim Fathy Balah
Aluminum phosphide is a highly toxic compound (oral LD50: 11.5 mg/kg), that is used as a fumigant, insecticide, and rodenticide (Bingham et al. 2001). AlP is commonly available as tablets, therefore, it is described as “rice tablets” or “wheat bills” (trade names: Quickphos, Phostoxin, Bhostoxin, Phostek, Phosphume). Each rice tablet is three grams and is constituted of 56% AlP and 44% aluminum carbonate and releases one gram of PH3 upon exposure to moisture. The AlP tablet is often grayish; however, it could be green or brown. AlP is also available as pellets (trade names: Quickphos, Alphos, Cellphos). Each 0.6 g pellet releases 0.2 grams of PH3 gas upon exposure to humidity. After the release of PH3 gas from AlP formulas, nontoxic aluminum hydroxide residues are left behind (Moghadamnia 2012). The fatal dose of AlP for a 70 kg adult is 150–500 mg for oral intake. Regarding inhalational exposure, the permissible exposure limit (PET) of AlP is 0.3 ppm throughout an 8-h shift. The short-term exposure limit (STEL) is one ppm, and the immediate threat to life and health is 200 ppm. The 400–600 ppm range has been identified for the deadly dose in 30 min (Environmental Protection Agency 1998; Bingham et al. 2001).
Application of multiple occupational health risk assessment models in occupation health risk prediction of trichloroethylene in the electroplating and electronics industries
Published in International Journal of Occupational Safety and Ergonomics, 2023
Shibiao Su, Zhiming Liang, Sheng Zhang, Haijuan Xu, Jinru Chen, Zhuandi Zhao, Meibian Zhang, Tianjian Wang
Based on the field investigation, the number of workers, duration of work, daily usage of TCE, exposure time, engineering protection measures and PPE were collected for all industries. Air sampling and laboratory tests for TCE were performed according to the standard in China described in GBZ 159-2004 ‘Specifications of air sampling for hazardous substances monitoring in the workplace’ [21] and GBZ/T 160.46-2004 ‘Methods for determination of halogenated unsaturated hydrocarbons in the air of workplace’ [22]. The 8-h time weighted average concentration (C-TWA) and short-term exposure concentration (C-STEL) were tested. According to Chinese standard requirements GBZ 2.1-2007 ‘Occupational Exposure Limits for Hazards in the workplace. Part 1: chemical hazardous agents’ [23], the permissible concentration time-weighted average (PC-TWA) for TCE is 30 mg/m3 and the permissible concentration short-term exposure limit (PC-STEL) is allowed to be less than twice the PC-TWA.
Washout kinetics of ethanol from the airways following inhalation of ethanol vapors and use of mouthwash
Published in Clinical Toxicology, 2020
Lena Ernstgård, A. Pexaras, G. Johanson
We measured the elimination of breath ethanol in volunteers after local exposure by inhalation and via mouthwash. Fingertip capillary blood samples collected after the exposures confirmed that the systemic uptake of ethanol was negligible. The decrease in BrAC was mono-exponential after both exposures, but with a five-fold slower decline after mouthwash (average half times of 1.9 versus 0.42 min). In addition, the intial BrAC was – 30-fold higher after mouthwash (4.3 versus 0.14 mg/L). The exposure levels in our study (763–950 mg/m3) were similar to the Swedish 8-h OEL of 1000 mg/m3 (500 ppm), the 15-min STEL being 1900 mg/m3 (1000 ppm). The OELs and STEL differ somewhat between countries, e.g., in Germany they are 380 mg/m3 (200 ppm) and 1520 mg/m3 (800 ppm), while the American Conference of Industrial Governmental Hygienists (ACGIH) recommends a STEL of 1880 mg/m3 (1000 ppm). The ethanol toxicokinetics are first-order at these low concentrations, therefore a doubling of the exposure level would result in double BrAC levels at any time point, with no change in half time. Thus, the time for BrAC to fall below the statutory limit would take one half time longer. Likewise, the BrAC levels after mouthwash will depend on the ethanol percentage in the mouthwash (as well as volume and duration). In our study, we chose to use the product with the highest ethanol content available on the Swedish market, i.e., with 22%. In other studies, mouthwash with ethanol content between 4 and 30% has been used [5,13].