Kurt Andersson

Immunoaffinity column clean-up for the high-performance liquid chromatographic determination of aflatoxins B1, B2, G1, G2, M1 and Q1 in urine.

A method for the determination of aflatoxins B1, B2, G1, G2, M1 and Q1 in human urine has been developed. The 10-ml urine samples were automatically cleaned up on immunoaffinity columns and analysed by high-performance liquid chromatography (HPLC), including post-column derivatization with bromine and fluorescence detection. Average aflatoxin recoveries were: B1 103%, B2 106%, G1 98% and G2 96% in the range 6.8-73 pg/ml of urine and M1 103% and Q1 100% in the range 18-97 pg/ml of urine. The relative standard deviations were all between 1% and 21%. The determination limits of aflatoxins in urine were 6.8 pg/ml for B1, B2, G1 and G2 and 18 pg/ml for M1 and Q1.

High‐performance liquid‐chromatographic determination of fgrivialdehyde in air in the ppb to ppm range using diffusive sampling and hydrazone formation

Abstract A diffusive sampler has been developed and validated for determination of formaldehyde with a sensitivity of 5 ppb in an 8‐h sample. The sampler consists of a 20×45 mm filter impregnated with 2,4‐dinitrophenyl‐hydrazine and phosphoric acid and mounted in a polypropylene housing. The uptake rate was determined to be 25.2 ml‐min‐1, with a relative standard deviation of 6.7%. The uptake rate was independent of formaldehyde concentration (0.07–3.7 mg‐m‐3), sampling time (15–480 min), relative humidity (10–80%). The effect of wind velocity (0.05–1.0 m.s‐1) was also studied. The sampler was also validated in the field.

Determination of volatile amines in air by diffusive sampling, thiourea formation and high-performance liquid chromatography

Abstract A diffusive sampling method for the determination of primary and secondary amines in air was evaluated. The sampler consists of a filter, impregnated with naphthyl isothiocyanate, in a polypropylene housing. A substituted thiourea is formed in situ during sampling, which is desorbed and determined by high-performance liquid chromatography. The sampler was validated for the sampling of methylamine, allylamine, isopropylamine, n -butylamine and dimethylamine using standard amine atmospheres, and the uptake rates for the five amines were determined. The effect on uptake rate of amine concentration, sampling time and relative humidity was investigated and found to be small. The detection limits for the amines studied are below 50 μg/m 3 for an 8-h sample.

Analysis of fatty acids. A new method for characterization of moulds

Aspergillus flavus, A. oryzae, A. fumigatus, Penicillium roqueforti, P. verrucosum, P. viridicatum, Mucor hiemalis, M. plumbeus and M. piriformis were cultivated on standardized media. The spores were harvested and the fatty acids of the spores transesterified. The fatty acid methyl esters were analysed by gas chromatography, and the fatty acids data were subjected to multivariate statistical analyses by SIMCA (Soft Independent Modelling of Class Analogies) pattern recognition. The results showed that this method enables various species of the moulds to be identified in a reproducible way.

Determination of aflatoxins in airborne dust from feed factories by automated immunoaffinity column clean-up and liquid chromatography

Abstract A method for the determination of aflatoxins in airborne dust is described. The dust samples were extracted with acetone-water, cleaned up on immunoaffinity columns and analysed by HPLC, including a post-column derivatization reaction with bromine and fluorescence detection. The method was evaluated with filters spiked with 62–595 pg of aflatoxins B 1 , B 2 , G 1 and G 2 , respectively. Average aflatoxin recoveries for B 1 , B 2 , G 1 and G 2 were 97, 101, 87 and 84%, respectively. The method was used for airborne dust collected at feed factories. The detection limit was 3.1 ng/g dust for aflatoxins B 1 , G 1 and G 2 and 1.8 ng/g for aflatoxin B 2 , for a 10-mg dust sample.

Exposure to Ski-Wax Smoke and Health Effects in Ski Waxers

Abstract Downhill as well as cross-country skis have undergone revolutionary technical development in recent decades. Parallel with innovations in ski bottoms, new types of ski wax have appeared on the market. At the same time complaints have been voiced increasingly by those who wax skis. We followed five male professional waxers at work in this combined chemical and medical study. Chemical analysis of some common ski waxes showed that they consist mainly of a mixture of straight-chain aliphatic hydrocarbons. Some waxes also contain mixtures of silicone compounds in unknown amounts. One brand consisted entirely of a polytetrafluoroethylene (PTFE). The individual components vaporize on heating, and on cooling in the air they condense rapidly to smoke consisting of particles less than 1 μm in diameter. Particles of this size might reach down into the pulmonary alveoli on inhalation. All ski waxes may be expected to behave in the same way, whether they contain paraffin, PTFE, or silicone. The results show t...

Monitoring of Parts-Per-Billion Levels of Formaldehyde Using a Diffusive Sampler

A diffusive sampler for formaldehyde originally designed for use in personal monitoring of worker exposure has been evaluated for static measurement of low formaldehyde levels in indoor air. The sampler consists of a 37-mm glass fiber filter impregnated with 2,4-dinitrophenylhydrazine and phosphoric acid and mounted in a polystyrene filter cassette. Formaldehyde is sampled by controlled diffusion and subsequent hydrazone formation on the filter. The hydrazone is eluted from the filter with acetonitrile and analyzed by liquid chromatography and a UV detector. The diffusive sampler was evaluated for static (area) sampling in several industries, offices, and homes with formaldehyde levels of 6-200 ppb. Results from diffusive samplers were compared with results from pumped samplers. Even at low wind velocities (less than 0.01 m.s-1) there was good agreement between pumped and diffusive samples. The sensitivity will be 1 ppb in a 24-h sample, making the sampler especially useful for indoor air monitoring of low formaldehyde levels.

Automated sample clean-up with solid-phase extraction for the determination of aflatoxins in urine by liquid chromatography.

An automated extraction and clean-up procedure was developed for the determination of aflatoxins in human urine at the 50 pg/ml level. Aflatoxins B1, B2, G1 and G2 are captured on C2 extraction columns and simultaneously cleaned up with the aid of a robotic system. The processed samples are analysed by reversed-phase high-performance liquid chromatography. Fluorescence detection was enhanced for aflatoxins B1 and G1 using factorial design optimization of the post-column reactor. Silylation of the glass vials used in the robotic system was of the utmost importance. With non-silylated glass vials, up to 75% of the analytes were lost. Average aflatoxin recoveries were B1 95%, B2 90%, G1 93% and G2 89%.

Determination of Chemical Composition and Mutagenicity in Particles from Chainsaw Exhaust. Experimental Set-Up, Stability and Results from Two Different Fuels

A dilution tunnel for sampling of particles and gaseous emissions in chainsaw exhaust was constructed and tested for reproducibility. In addition the equipment was used to measure chainsaw emissions when using two different fuels, aliphatic petrol with synthetic lubricating oil and regular lead-free petrol with mineral lubricating oil. The content of polycyclic aromatic hydrocarbons (PAH) and the mutagenicity of sampled particles were measured as well as the concentration of carbon monoxide (CO), nitrogen oxides (NOx) and aldehydes in the exhaust. Particles were sampled isokinetically and collected on a filter followed by two polyurethane foam plugs (PUF) in series for sampling of the semivolatile components. PAH were analysed by a coupled liquid chromatography – gas chromatography (LC-GC) system and mutagenicity testing was carried out by using Ames Salmonella assay. The measured physical parameters as well as the particulate, semivolatile and gaseous emissions showed that reproducible measurements of exhaust emissions could be achieved using this experimental set-up. In terms of mutagenicity when testing for reproducibility, a small but significant effect was observed for the Salmonella strains TA98 and TA100 in the absence of a metabolizing system, both for the particulate phase and the semivolatile components. A significant difference was seen between the two different fuels tested, the conventional petrol with mineral oil having 5-10 times higher concentrations of different PAH compounds and a much higher mutagenic effect for all strains. This difference was seen both for the particulate phase and the semivolatile components.

Determination of Tertiary Amines in Air

Abstract Methods have been developed for air sampling of gaseous tertiary amines on solid sorbents. Sampling was performed at three different air levels and at 20 percent and 85 percent relative air humidity, respectively. Desorption was carried out by solvent extraction prior to high-resolution gas chromatographic analysis with flame ionization or nitrogen-phosphorus detection. Seven amines, differing in the length and shape of the carbon chains, were selected for the study and divided into three groups. The members of the first group, consisting of dimethylethylamine (DMEA), methyldiethylamine (MDEA), and triethylamine (TEA) were collected using charcoal tubes and desorbed with 5 percent ethanol in dichloromethane. The amine air levels were 1, 10, and 50 ppm. The recoveries of these amines were 92–100% (n = 6, RSD = 1–4%). Storage studies (5 days at room temperature followed by 9 days in a freezer) showed recoveries of 87 percent (DMEA), 89 percent (MDEA), and 82 percent (TEA). Determination of DMEA in ...