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J A Groves

Publications and source records attributed to J A Groves.

14 recordsLinked to original sources
PubMed2003

Occupational exposure to metalworking fluid mist and sump fluid contaminants.

This paper summarizes the analytical and occupational hygiene findings from a recent survey of occupational exposure to metalworking fluids (MWFs) in the engineering industry. The aim of the survey was to link MWF mist exposure measurements with particular engineering processes and controls, and utilize the data obtained to develop exposure standards. At the same time the opportunity was taken to assess fluid management and control, including bacterial and fines contamination in the machine sumps. In general, occupational exposure to mineral oil MWF mist was controlled to <3 mg/m(3) (8 h time-weighted average) and to <1 mg/m(3) for water-mix MWF mist (in terms of the concentrate). These exposure values do not necessarily represent best practice, but are believed to be achievable and representative of industry as a whole. Gravimetric analysis of the total inhalable particulate was found to be a good predictor of mineral oil MWF mist but not for water-mix MWF mist. Grinding and drilling operations produced higher exposures than turning and milling for water-mix fluids. There were insufficient data to compare machining operations for mineral oil MWFs. On the whole, fluid management was found to be poor, with most sites failing to meet industry good practice or Health & Safety Executive (HSE) standards. Some of the operating procedures utilized were deficient or unsatisfactory. Poor standards of fluid management were found at all sizes of company. High levels of bacteria, endotoxin and fines were found in sumps, and control of other factors, such as water-mix fluid concentration, was often poor. Mineral oils had higher levels of fines than water-mix fluids (medians of 395 and 18 mg/l, respectively), and grinding produced high levels of fines in both types of MWF. Many water-mix sumps contained bacterial levels of >1 x 10(6) CFU/ml, and endotoxin levels of >100 000 EU/ml were not uncommon. The median values were 109 000 CFU/ml and 8039 EU/ml, respectively. Mists could potentially contain extensive contamination from bacteria and endotoxin. Analysis of the data suggests that sumps operating under typical conditions for machining (a temperature of 20 degrees C, a pH of 9 and a fluid strength below 10%), also appear to provide optimum conditions for the proliferation of bacteria. Low levels of benzo[a]pyrene (median 0.03 micro g/g) were found in the mineral oils, and low levels of N-nitrosodiethanolamine (median 0.4 micro g/ml) were found in the water-mix MWFs. The results of this work will contribute to guidance from the HSE, setting out accepted industry good practice, including guide values for MWF mist and sump fluid contaminants, with significant emphasis on sump fluid management (maintenance and monitoring), as well as control issues.

Aerosols↗
PubMed2000

Mineral oil metal working fluids (MWFs)-development of practical criteria for mist sampling.

Not all mineral oil metalworking fluids (MWFs) in common use form stable airborne mists which can be sampled quantitatively onto a filter. This much has been known for some time but no simple method of identifying oils too volatile for customary filter sampling has been developed. Past work was reviewed and experiments were done to select simple criteria which would enable such oils to be identified. The sampling efficiency for a range of commercial mineral oil MWF were assessed by drawing clean air through spiked filters at 2 l. min(-1) for periods up to 6 h before analysis. The physical properties of MWF are governed by their composition and kinematic viscosity was found to be the most practical and easily available index of the potential for sample loss from the filter. Oils with viscosities greater that 18 cSt (at 40 degrees C) lost less than 5% of their weight, whereas those with viscosities less than 18 cSt gave losses up to 71%. The losses from the MWF were mostly aliphatic hydrocarbons (C(10)-C(18)), but additives such as alkyl benzenes, esters, phenols and terpene odorants were also lost. The main recommendation to arise from the work is that filter sampling can be performed on mineral oils with viscosities of 18 cSt (at 40 degrees C) or more with little evaporative losses from the filter. However, sampling oils with viscosities less than 18 cSt will produce results which may significantly underestimate the true value. Over a quarter of UK mineral oil MWFs are formulated from mineral oils with viscosities less than 18 cSt (at 40 degrees C). The problem of exposure under-estimation and inappropriate exposure sampling could be widespread. Further work is being done on measurement of mixed phase mineral oil mist exposure.

Humans↗
PubMed1999

Determination of hydroquinone in air by high performance liquid chromatography.

A method for measuring hydroquinone in air was evaluated, both in the laboratory and in the workplace. The method involved sampling the inhalable fraction onto a filter contained in a multi-holed sampler with a back-up of Tenax TA, followed by desorption into acetonitrile and analysis by High Performance Liquid Chromatography. It was shown to be effective at measuring hydroquinone over the range 0.1 to 2 times a concentration of 0.5 mg/m3 for 8 h.

Air Pollutants, Occupational↗
PubMed1999

Long-term alcohol consumption in the rat affects femur cross-sectional geometry and bone tissue material properties.

BACKGROUND: Alcohol consumption previously has been demonstrated to reduce the density and strength of cortical bone of young, actively growing rats. Osteoblast activity and trabecular bone volume were also significantly lower. A germane question arising from these studies is whether the detrimental effects would persist into adulthood. To address this issue, a long-term study was undertaken with animals that consumed alcohol throughout their life and into old age. METHODS: One-month-old female Sprague-Dawley rats were divided into three diet groups: alcohol-fed, pair-fed, and chow-fed. The alcohol-fed animals received a modified Lieber-DeCarli diet that contained 35% ethanol-derived calories. The pair-fed group served as a caloric-equivalent control, and the chow-fed animals served as a completely untreated control. Animals were euthanized after five time periods on the diets that represented three stages of the life span: young (3 months), adult (6, 9, 12 months), and aged (18 months). The left femur was isolated and mechanically tested in 3-point bending for mechanical properties. RESULTS: In the young animals, alcohol consumption produced dramatic reductions in both extrinsic (whole bone) and intrinsic (tissue material) properties, which is consistent with results from previous studies on growing rats. For the adult animals, however, the alcohol groups were only slightly lower and the differences were not statistically significant. The aged animals showed diminished properties due to alcohol, but only for the intrinsic material properties. The extrinsic properties remained similar to controls as a result of greater radial expansion in the femur diaphysis. Despite the cross-sectional areas being the same, this expansion gave rise to higher cross-sectional moment of inertia values in the alcohol animals. The thickness of the cortical wall was lowest in the alcohol group at all time points. CONCLUSIONS: Long-term alcohol consumption produced two major effects in the oldest animals studied: the quality of the cortical bone tissue was diminished, as evidenced by reduced elastic modulus and ultimate strength values, and the bone seemed to compensate for this by expanding the cross-section to produce larger cross-sectional moment of inertia values. The reduced bone tissue quality is consistent with the lower ash percent values in the alcohol animals, but other factors such as the quality of the collagen and mineral crystal may also be important contributors.

Age Factors↗
PubMed1998

The development of an improved method for the determination of coal tar pitch volatiles (CTPV) in air.

Test samples were collected at a range of sites using the MDHS 68 sampler, a 7-hole sampler, and a cyclone respirable-dust sampler. Glass fibre, Zefluor, Fluoropore and silver (0.8 and 5 microns) filters were compared for weighing error, handling characteristics, and amount collected. The effects of a carbon back-up, of extraction solvent, and of analytical method were studied. The current HSE method for the sampling and analysis of coal tar pitch volatiles, MDHS 68 has been reviewed. It is recommended that the MDHS 68 sampler be replaced by a 7-hole head containing a silver or PTFE filter (approximately 1 micron pore size), with a graphitized carbon back-up if efficient collection of 2 to 4-ring PAHs is required. Cyclohexane is recommended as the extraction solvent. Methods of analysis which quantify the fume as a whole (MDHS 68, u.v., ELSD) were shown to give a response which varied according to the type of CTPV generating process. Therefore analysis of specific PAHs of occupational interest, by GC-MS or HPLC is recommended.

Air Pollutants, Occupational↗
PubMed1998

Measurement of airborne cyanoacrylates.

The behaviour of common alkyl-2-cyanoacrylates in air has been investigated. Increasing humidity was found to increase the rate of polymerisation, although polymerisation is not instantaneous, even at high humidities. Sampling methods for these compounds have been studied and we are able to recommend a pumped Tenax sampling tube, although certain sampling limitations apply, notably that specified flow rates must be applied and that a maximum sampling time of four hours is recommended. Significant errors can occur if sampling is performed outside the range of conditions specified. Upon completion of sampling the tube is desorbed into 0.2% phosphoric acid in acetonitrile. The resulting solution is analysed by HPLC.

Air Pollutants, Occupational↗
PubMed1997

International round robin tests on the measurement of carbon in diesel exhaust particulates.

OBJECT: Diesel soot has been recognized as probably carcinogenic to humans. Elemental carbon (also called black carbon) in soot is considered at the moment as the most significant surrogate to be measured for assessing the exposure to this pollutant. Its analysis is done by combustion in an oven and determination of the CO2 formed, after elimination of the organic fraction of the soot by heating and/or by solvent extraction. The analysis allows determination of both fractions of the soot: "elemental carbon" (EC) and organic carbon (OC). The sum of EC and OC is called TC (total carbon). METHOD: An informal European coordination group organized two round robin tests on filter samples collected from diluted diesel emissions. The first round (RRT1) was performed on 13 different samples analyzed by ten laboratories. The range of loading was 2.5 to 150 micrograms/cm2 of EC. No evaluation of the precision within laboratories could be made since each laboratory gave only one result per sample. Therefore a second round (RRT2) was organized with two samples and a blank filter sent in several portions to 11 laboratories. It should be stressed that each laboratory used its own method and that no standardization was planned at this stage. RESULTS: Results of RRT1 showed that the coefficient of variation between laboratories decreased with higher loading and was around 10% to 15% for EC above about 20 micrograms/cm2. Dispersion of the results varied and it appeared that the way OC is removed from the soot is probably the most important factor of influence. The correlation between the laboratories was good as a whole but some systematic differences could be detected. Besides the different techniques to remove the organic carbon, the pretreatment of the filter by HCl (either as a vapor or as a solution) to remove the inorganic carbonates (potential interference sources), is probably also a significant factor of influence in the dispersion of the results between laboratories. It is not yet clear from these results whether the "environmental" laboratories give different results from the "occupational" laboratories, but it is clear that their objectives differ since for the "environmentalists", EC is not a specific marker of diesel emmissions, in contrast to the "occupationalists". CONCLUSION: It can be concluded that, although significant differences exist between laboratories they can be attributed mainly to the narrow distribution of the results within a single laboratory, and that the overall agreement of the results for EC and TC is fairly good. These results obtained with pure diesel engine emissions, should be complemented by field samples, but they have already achieved relevant findings in the performance of the procedures used to assess exposure to diesel soot.

Air Pollutants↗
PubMed1996

Chemical pollutants in X-ray film processing departments.

A survey of X-ray film processing departments revealed the main airborne contaminants to be sulphur dioxide and acetic acid at concentrations of about 0.1 ppm. Glutaraldehyde was not detected either in the ambient air or in the exhaust duct from an automatic film processor. Laboratory studies confirmed sulphur dioxide and acetic acid as the main headspace constituents above working strength processing solutions but glutaraldehyde and butyraldehyde were also detected.

Acetates↗
PubMed1996

On-site monitoring of personal exposure to tetrachloroethylene at dry cleaning establishments.

Methods for monitoring personal exposure to tetrachloroethylene vapour in the dry cleaning industry have been investigated. A Draeger diffusive colorimetric gas detector tube and the Delta vapour detection system manufactured by Sabre Gas Detection were both shown to be suitable for preliminary on-site monitoring. A range of short-term pumped colorimetric tubes were also shown to perform well under a range of environmental conditions. Data on laboratory evaluations and field trials are presented.

Air Pollutants, Occupational↗
PubMed1991

Gases in agricultural slurry stores.

The evolution of gases during the handling of animal slurry was investigated at five sites. Particular attention was paid to the mixing and emptying operations since it is when performing these that personnel are most likely to be at risk of exposure. The main hazard was found to be high transient concentrations of hydrogen sulphide presenting in some cases a serious acute toxicity problem. Time-weighted average exposures did not generally indicate any long-term exposure risk. Other features noted were the evolution of ammonia and methane, although not at high levels, and some increase in the carbon dioxide concentration. Some reduction in oxygen concentration was measured, but generally the risk of poisoning by hydrogen sulphide was more serious than the risk of asphyxiation.

Ammonia↗
PubMed1990

Evaluation of a diffusive sampler for formaldehyde.

A diffusive sampling system, using a commercially available liquid sorbent badge, has been evaluated for the determination of airborne formaldehyde concentrations according to the U.K. Health and Safety Executive protocol. The results of laboratory and field experiments are presented. The results obtained using the diffusive sampler during field measurements were about 10% higher overall than those obtained using a conventional pumped sampler.

Diffusion↗
PubMed1989

Gases in forage tower silos.

Measurements of hazardous gas concentrations in forage tower silos are described. The problems associated with sampling in silos, the identity and distribution of gases and their rate of evolution, and the effects of forced and natural ventilation are considered. Particular attention is given to conditions at times when entry to the silo by farm personnel is likely and the possibility of farmers carrying out gas measurements is discussed.

Air Pollutants, Occupational↗
PubMed1982

Interdisciplinary treatment of encopresis in individuals with developmental disorders: need and efficacy.

The specific target behavior of encopresis in individuals with mental retardation and developmental disorders (MR/DD) is not well-defined in the literature on encopresis or in the literature on specific interventions with MR/DD populations. The criteria for establishing a diagnosis of encopresis in individuals with MR/DD are not clear. The literature on encopresis was reviewed for two factors: (1) definitions according to three major definitional criteria of age, defecation patterns and etiology; and (2) the relationship between etiology and intervention in specific, MR/DD, and nonspecific populations. This review yielded no clinical description of encopresis in MR/DD children, no guidelines for differentiating encopresis from generalized developmental delay and no substantive treatment guidelines. Although no definitions or treatment formulations specific to MR/DD were identified, information and definitional guidelines derived from the general literature on encopresis are relevant to identification, definition and treatment issues for MR/DD populations. Interdisciplinary or team approaches are appropriate for individuals with multiple problems or developmental disorders and intractable encopresis. An interdisciplinary approach, neurodevelopmental-behavioral intervention, which was successfully employed with a 5-year-old encopretic child with multiple developmental problems, is described.

Age Factors↗