PubMed Health⌕ Search

SEARCH · PubMed Health

Results for “Hazardous Substances”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 19 recordsLinked to original sources
PubMed1992

[Assessment of occupational exposures to industrial hazardous substances. V. A proposed method for evaluating employee's exposure averages (8-h TWAs) using a single day measurement].

Daily exposure averages (8-h TWAs) to hazardous substances may vary considerably day to day, even though a worker is engaged in the same job. Previously we proposed a method to evaluate a long-term exposure condition with interday fluctuation using some exposure measurements. As it is assumed that 8-h TWAs are log-normally distributed, geometric standard deviation (sigma g) representing true interday fluctuation of 8-h TWAs should be estimated. If a single day's 8-h TWA of a worker is measured, sigma g of his own distribution of 8-h TWAs cannot be estimated. Therefore, to evaluate a long-term condition using a single day's 8-h TWA, representative sigma g in all industrial workplaces must be determined beforehand. To investigate sigma g observed in many industrial workplaces, two days' 8-h TWAs of each worker were measured in a week on 260 workers exposed to 19 hazardous substances. Sg2 (geometric standard deviation estimated by two samples) ranged from 1.00 to 8.22 with a median of 1.47 and a 90% upper limit of 2.47. Transforming Sg2 into sigma g, median and 90% upper limit of sigma g were 1.75 and 2.47, respectively. According to a classification scheme in the proposed method, exposure levels (I to III) were calculated using sigma g of 1.75 and 2.47. A long-term exposure condition to hazardous substances can be evaluated by comparing a single day's 8-h TWA with the exposure levels.

Environmental Monitoring↗
PubMed1988

Hazardous Substance Center: a poison center's workers right to know program.

Workers Right To Know (WRTK) legislation has been enacted in several states. It is landmark advocacy legislation for employees and communities who may be exposed to hazardous chemicals, but it is also a complex and costly problem for business, industry, and nonprofit organizations. The Hazardous Substance Center (HSC), a division of the Pittsburgh Poison Center, was created to develop and implement programs to enable the business community to comply with the requirements of WRTK legislation. Specifically, the HSC provides the client with a 24-hour toxicology resource which objectively assists employees in the interpretation of the health-related effects information on material safety data sheets (MSDS) and assists them and medical professionals in the management of acute and chronic exposures. A variety of online databases and reference materials are utilized to respond to these inquiries. Each case is documented using the AAPCC Report Form. Data is analyzed to identify trends which can be used to assist the client in complying with the educational component. The HSC also provides a labeling program to the client to identify and classify hazardous substances. The service is provided for an annual contractual fee and creates an additional source of poison center revenue.

Humans↗
PubMed1989

[Assessment of occupational exposures to industrial hazardous substances. IV. A proposed method based on one-sided tolerance limits].

Occupational exposures to potentially hazardous substances may vary considerably because of interday environmental behavioral fluctuations in the contaminant concentration. Such occupational exposures including those of non-monitored days can be theoretically evaluated by the following three ways: 1) assessment of geometric mean and geometric standard deviation, 2) assessment of arithmetic mean, and 3) assessment of upper limits of daily exposure distribution. In our previous report, an evaluation method on 95% upper limit or arithmetic mean of exposures was proposed. The method is useful, particularly, in case where only one or two days are being monitored, but may provide an approximate estimate because of statistical assumption. A sampling and decision scheme using one-sided tolerance limits (OTL) proposed by Tuggle (1982) can precisely evaluate the upper limits of exposures. However, many cases would be evaluated as "no decision," unless the sample size is extremely large in number. We developed a revised method based on OTL for assessment of occupational exposures. The characteristic features of this method can be summarized as follows: 1. Upper limits of lognormally distributed 8-h exposure concentrations can be evaluated in comparison with an established standard. 2. A third OTL factor was introduced into Tuggle's scheme in which two OTL factors were used. A comparison between the upper limits of exposures and the standard can be made at 50% confidence level with the factor. The factor was calculated using non-central t-distribution. 3. The usefulness of the third OTL factor in the assessment of occupational exposures was confirmed by examining the performance characteristics of the method.(ABSTRACT TRUNCATED AT 250 WORDS)

Data Interpretation, Statistical↗
PubMed1991

Control of substances hazardous to health (COSHH) regulations and hospital infection.

Recently enacted UK legislation has focused attention on risks to the health of health care staff engaged in control of infection procedures. The Regulations comply with a European Community (EC) directive. Occupational exposure to disinfectants and sterilants is widespread and requires close attention to ensure that it is adequately controlled. The aldehydes in particular present serious health risks including respiratory sensitization. The Regulations provide a framework for systematically identifying and controlling health risks from any 'substance hazardous to health'. This includes microorganisms as well as chemical agents. There are clear implications for hospital infection control in the UK and other EC countries. Consideration needs to be given to staff health and safety when selecting disinfection/sterilization procedures in addition to the effective control of infection.

Cross Infection↗
PubMed1988

[Assessment of occupational exposures to industrial hazardous substances. II. Interday fluctuations of the daily exposure averages among workers exposed to lead].

An assessment of the employee's exposures to industrial hazardous substances using the proposed method described earlier was conducted on 49 workers exposed to lead. As it is assumed that the daily exposure averages are lognormally distributed, geometric standard deviation (sigma g) representing true interday fluctuations of the daily exposures was estimated by personal exposure measurements of every worker for two consecutive days. The estimates (Sg) ranged from 1.00 to 5.35 with a median of 1.4 and a 90% upper limit of 2.4. According to a classification scheme in the proposed method, exposure levels (I to III) were calculated using sigma g of 1.4 and 2.4. An exposure class based on a single day measurement was evaluated and compared to that based on measurements for two consecutive days. As a result, the decision of the exposure levels and classes from only one day monitoring could be made by using both sigma g of 1.4 and 2.4, representing ordinary and high interday fluctuations, respectively. More accurate estimate of geometric standard deviation of interday fluctuations by exposure monitorings would provide a more reliable assessment of the worker's long-term exposure situation.

Data Interpretation, Statistical↗
PubMed1988

[Assessment of occupational exposures to industrial hazardous substances. I. A proposed method based on interday fluctuation of contaminant concentrations for evaluating employee's exposure averages (TWAs)].

Occupational exposures to potentially hazardous substances may vary considerably because of factors such as sampling and analytical errors, and intraday and interday environmental fluctuations in contaminant concentration. Of these factors, day-to-day environmental fluctuations most likely affect daily exposure averages over days, weeks, months or years. A new method based on day-to-day fluctuations of daily exposure averages (geometric standard deviation) was developed for making reliable assessment of the employee's exposure situation. It is assumed that daily exposure averages of a worker are lognormally and independently distributed statistically. Finally, a classification scheme on the basis of n days measurements is presented. 95% upper limit or arithmetic mean of individual exposure averages (8-h TWAs) can be evaluated in comparison with an established standard. The method may provide an approximate estimate because of statistical premise, but it can be utilized for practical purposes, particularly, in case where only one or two days are being monitored. An action level concept based on random sampling and analytical errors and interday variations developed by OSHA/NIOSH, and a sampling and decision scheme based on one-sided tolerance limits proposed by Tuggle (1982) are also discussed.

Data Interpretation, Statistical↗
PubMedDate not supplied

The problems of environmental hazardous substances: an overview.

It was decided to present an overview of problems of environmental hazardous substances by selecting three areas of concern which represent different aspects of the overall subject. All three are topics of great interest at the present time. They provide examples of different causes of the hazards and different approaches to their resolution or containment. Aerial and water contamination by radon gas are a natural hazard only recently recognized. Radon can be contained, but it will require cooperative action and expenditure. Herbicides are a continuing problem demanding increased research activity to establish risk-benefit decisions. Pollution of estuaries and oceans require new development of models for establishing safe levels of some pollutants and prohibition of others.

Air Pollutants, Radioactive↗
PubMed1989

[Assessment of occupational exposures to industrial hazardous substances. III. On the frequency distribution of daily exposure averages (8-h TWA)].

A method based on interday fluctuation of contaminant concentrations for evaluating employee's exposure averages (8-h TWAs) was proposed in our previous report. The method was established on the assumption that daily exposure averages of the workers are lognormally distributed in actual workplaces. The study was conducted to elucidate whether the distribution of daily exposure averages is statistically lognormal or not and to examine the relationship between sample geometric standard deviation (sg) of worker's daily exposure averages and its estimate (sg2) calculated by measurements for two consecutive days. These are critical for our proposed method. The data on daily exposure concentrations over five to six weeks were collected from workers exposed to cobalt, acetone, n-hexane, toluene, xylene, ethylbenzene and ethylacetate. The data on organic lead, inorganic lead and mercury exposures reported by Cope et al. and Lindstedt et al. were also used for the study. The result can be summarized as follows: 1. Lognormal distribution of daily exposure averages was confirmed by plotting on normal probability paper and chi 2-test. 2. Median of sg2 on daily exposure averages obtained from individual worker was smaller than sg. 3. sg calculated by a set of measurements for two consecutive days in every worker can be corrected by the equation: (sg2) 1.48 in obtaining a better estimate of sigma g. 4. Statistical analysis on daily exposure averages of all workers showed that median of sg2 was smaller than that of sg, and 88% upper limit of sg2 was equal to that of sg. 5. Therefore, in evaluating TWA obtained by only single day's measurement using the proposed method, median of sg representative of industrial hazardous substance exposure workplaces could be also corrected by the equation described above. However, correction of 90% upper limit of sg2 is not necessary.

Data Interpretation, Statistical↗
PubMed1987

Untangling causation issues in law and medicine: hazardous substance litigation.

Judges and juries are increasingly being asked to settle questions about disease caused by hazardous products. With the growth of litigation on toxic substances and unsafe products, more and more courts must wrestle with the complicated scientific proof of the relation between exposure and disease or injury. This proof frequently involves the use of probabilistic evidence in the form of statistical tests and epidemiologic studies. Anglo-American law relies on deductive notions of causation and is suspicious of probabilistic evidence of causation. As a result, court decisions of hazardous substance cases are sometimes based on a confused understanding of the critical causal connection. Physicians who testify in such cases, either as the treating doctor or as expert witnesses, must be aware of the court's difficulty with probabilistic evidence. In addition, physicians must state clearly the role of such evidence in the identification of a hazardous substance as the cause of a disease or injury.

Consumer Product Safety↗
PubMed1990

[Improvement in standardization of hazardous substances].

The article traces the reasons accounting for limitations in practical application of MACs, proposes alternative approaches to MAC norming with wider use of computer technology, epidemiological surveys, particularly in ecologically unfavourable areas. It is stressed that hazardous substances norming must be performed by the hygienists.

Environmental Pollutants↗