[Asbestos related cancers: burden and recognition as occupational diseases]. / Cancers liés à l'amiante : fardeau et reconnaissance comme maladies professionnelles.

Although asbestos has been banned in Switzerland since 1989, diseases caused by asbestos are still present and increasing today. In Switzerland, per year, occupational exposure to asbestos is responsible for approximately 135 deaths from mesothelioma and 930 deaths from lung cancer, though the latter is rarely recognized as an occupational disease. Taking an occupational history is essential for all such diagnosis, especially in smokers, whose risk of lung cancer increases due to the synergistic effect of asbestos and tobacco exposure. The medical practitioner can play an important role in occupational diseases being recognized as such, which is essential for the reimbursement of medical expenses by the accident insurance companies and the allocation of indemnities and pensions for the patient or their family.

Bien que l'amiante soit interdit en Suisse depuis 1989, les maladies provoquées par l'amiante sont aujourd'hui toujours présentes et en augmentation. En Suisse, par année, l'exposition professionnelle à l'amiante est responsable d'environ 135 décès par mésothéliome et 930 par cancer du poumon ­ rarement reconnu comme maladie professionnelle. Lors de tout diagnostic, il est essentiel d'effectuer une anamnèse professionnelle, en particulier chez les fumeurs, qui voient leur risque de cancer du poumon augmenter en raison de l'effet synergique amiante-tabac. Le médecin praticien peut jouer un rôle important pour faire reconnaître une maladie comme professionnelle, indispensable pour la prise en charge des frais médicaux par les assurances-accidents ainsi que l'allocation d'indemnités et de rente pour le patient, voire sa famille.

[Risk assessment and management: between epidemiology and social acceptability]. / Évaluation et gestion des risques : entre épidémiologie et acceptabilité sociale.

Risk is a well-known concept in medicine and in epidemiology and its approach intend to be rational and measurable. Risk measurement makes it possible to communicate with a patient or a population the risk of occurrence of an event. However, it is often difficult to estimate accurately the probability of occurrence of an adverse event and there is therefore uncertainty. In addition, the notion of risk is not easy to grasp for most people. The same risk can be perceived very differently from one individual to another and this perception and understanding depends on psychological, social, cultural, historical and political factors. Understanding this social dimension of risk in clinical practice or in public health is essential to implement efficient risk management.

La notion de risque est bien connue en médecine et en épidémiologie et son approche se veut rationnelle et mesurable. Cette mesure du risque permet de communiquer à un patient ou à une population le risque de survenue d'un événement. Mais il est souvent difficile d'estimer avec précision la probabilité de survenue d'un événement et il existe donc de l'incertitude. De plus, la notion de risque n'est pas facile à appréhender pour la plupart des personnes. Un même risque pourra être perçu très différemment d'un individu à l'autre et ces perception et compréhension des risques dépendent de facteurs psychologiques, sociaux, culturels, historiques et politiques. Bien comprendre cette dimension sociale du risque est essentiel pour appréhender une gestion des risques, que ce soit en clinique ou en santé publique.

Probable aerosol transmission of SARS-CoV-2 in a poorly ventilated courtroom.

There is increasing evidence of SARS-CoV-2 transmission via aerosol; the number of cases of transmission via this route reported in the literature remains however limited. This study examines a case of clustering that occurred in a courtroom, in which 5 of the 10 participants were tested positive within days of the hearing. Ventilation loss rates and dispersion of fine aerosols were measured through CO2 injections and lactose aerosol generation. Emission rate and influencing parameters were then computed using a well-mixed dispersion model. The emission rate from the index case was estimated at 130 quanta h-1 (interquartile (97-155 quanta h-1 ). Measured lactose concentrations in the room were found relatively homogenous (n = 8, mean 336 µg m-3 , SD = 39 µg m-3 ). Air renewal was found to play an important role for event durations greater than 0.5 h and loss rate below 2-3 h-1 . The estimated emission rate suggests a high viral load in the index case and/or a high SARS-CoV-2 infection coefficient. High probabilities of infection in similar indoor situations are related to unfavorable conditions of ventilation, emission rate, and event durations. Source emission control appears essential to reduce aerosolized infection in events lasting longer than 0.5 h.

Estimation of Individual Exposure to Erythemal Weighted UVR by Multi-Sensor Measurements and Integral Calculation.

Ultraviolet radiation (UVR) can be hazardous to humans, especially children, and is associated with sunburn, melanoma, and the risk of skin cancer. Understanding and estimating adults' and children's UVR exposure is critical to the design of effective interventions and the production of healthy UVR environments. Currently, there are limitations to the ways computer modeling and field measurements estimate individual UVR exposure in a given landscape. To address these limitations, this study developed an approach of integral calculation using six-directional (up, down, south, north, east, and west) field-measured UVR data and the estimated body exposure ratios (ER) for both children and adults. This approach showed high agreement when compared to a validated approach using ambient UVR and estimated ER data with a high r-square value (90.72% for child and adult models), and a low mean squared error (6.0% for child model and 5.1% for adult model) in an open area. This approach acting as a complementary tool between the climatology level and individual level can be used to estimate individual UVR exposure in a landscape with a complicated shady environment. In addition, measuring daily UVR data from six directions under open sky conditions confirmed that personal dosimeters underestimate actual individual UVR exposure.

[Principles of prevention and precaution†: some guidelines for understanding them]. / Principes de prévention et de précaution†: quelques repères pour leur compréhension.

The COVID-19 pandemic highlighted, sometimes painfully, the stakes of decision-making in a context of significant uncertainty. Social distance, wearing a mask, confinement… difficult choices with significant health, social and economic impacts. To guide and justify our decisions, the principles of precaution and prevention have been used. Invoked like mantras to protect us from bad luck, are these two principles really a panacea for these situations ? Not sure… Beyond their intrinsic moral value and the rationality they bring to the decision-making process, their implementation suffers from serious limitations. Doesn't their use make us forget the essential ? The need to tackle the roots of the problem before ending up in an uncomfortable toss-up.

La pandémie de Covid-19 a mis en exergue, parfois douloureusement, les enjeux de la prise de décision dans un contexte d'incertitude importante. Distance sociale, port du masque, confinement… des choix difficiles dont les effets sanitaires, mais aussi sociaux et économiques sont conséquents. Pour guider et justifier nos décisions, les principes de précaution et de prévention ont été mis à contribution. Invoqués tels des mantras pour se protéger du mauvais sort, ces deux principes sont-ils réellement la panacée à ces situations ? Pas sûr… Au-delà de leur valeur morale intrinsèque et de la rationalité qu'ils apportent au processus décisionnel, leur mise en œuvre souffre de sérieuses limites. Leur usage ne nous fait-il pas oublier l'essentiel ? La nécessité de s'attaquer aux racines du problème avant de se retrouver dans un inconfortable pile ou face.

Facial exposure to ultraviolet radiation: Predicted sun protection effectiveness of various hat styles.

BACKGROUND/PURPOSE: Solar ultraviolet radiation (UVR) doses received by individuals are highly influenced by behavioural and environmental factors. This study aimed at quantifying hats' sun protection effectiveness in various exposure conditions, by predicting UVR exposure doses and their anatomical distributions. METHODS: A well-defined 3-dimensional head morphology and 4 hat styles (a cap, a helmet, a middle- and a wide-brimmed hat) were added to a previously published model. Midday (12:00-14:00) and daily (08:00-17:00) seasonal UVR doses were estimated at various facial skin zones, with and without hat wear, accounting for each UVR component. Protection effectiveness was calculated by the relative reduction in predicted UVR dose, expressed as a predictive protection factor (PPF). RESULTS: The unprotected entire face received 2.5 times higher UVR doses during a summer midday compared to a winter midday (3.3 vs 1.3 standard erythema dose [SED]) with highest doses received at the nose (6.1 SED). During a cloudless summer day, the lowest mean UVR dose is received by the entire face protected by a wide-brimmed hat (1.7 SED). No hat reached 100% protection at any facial skin zone (PPFmax : 76%). Hats' sun protection effectiveness varied highly with environmental conditions and was mainly limited by the high contribution of diffuse UVR, irrespective of hat style. Larger brim sizes afforded greater facial protection than smaller brim sizes except around midday when the sun position is high. CONCLUSION: Consideration of diffuse and reflected UVR in sun educational messages could improve sun protection effectiveness.

[« Heated ¼ tobacco products : what do you need to know ?] / Produits du tabac «chauffé¼ : que faut­il savoir ?

With the decline of conventional cigarette sales, tobacco companies developed and began marketing a new type of product that does not burn tobacco in 2015. These products, called « heated tobacco products ¼ (HTP), are marketed as potentially reduced risk products because their technology limits combustion and the generation of toxic compounds. However, the principal harmful compounds commonly measured in conventional cigarette smoke are also present in HTP emissions. Currently, few independent studies have verified the level of risk of these HTP, which raises important questions for the population and public health actors. This article aims to describes the current situation with regards to HTP.

Face à la diminution constante des ventes de cigarettes conventionnelles, l'industrie du tabac a développé et mis sur le marché depuis 2015 un nouveau type de produits qui ne « brûlent ¼ pas le tabac, dits produits du tabac « chauffé ¼ (heated tobacco products ou HTP). Ils sont vendus comme des produits à risques potentiellement réduits, du fait de leur capacité technique à limiter le processus de combustion et la génération de composés toxiques. Toutefois, les principaux composés toxiques émis par la fumée de cigarette conventionnelle sont aussi présents. Actuellement, très peu de recherches indépendantes existent pour vérifier le niveau de risque des HTP, ce qui soulève d'importantes questions parmi la population et les acteurs de santé publique. Cet article fait le point sur ces produits.

Ex vivo human skin permeation of methylchloroisothiazolinone (MCI) and methylisothiazolinone (MI).

Methylchloroisothiazolinone (MCI) and methylisothiazolinone (MI) are biocides used in many types of products such as cosmetics, paints, and cleaning agents. Skin contact is often encountered when using these products. Although MCI and MI are strong allergens and cause skin irritation, no scientific skin permeation study has been reported except for some unpublished data. Therefore, this study assessed the permeation of MCI and MI both separately and as a mixture through freshly dermatomed human skin (800 µm) in a flow-through diffusion cell system. Different concentrations of aqueous standards (1.5/1, 70/50, 150/35, and 750/175 µg/mL of MCI/MI) and various commercial products were assessed after 15-20 h of exposure. In parallel, the dose-dependent irritant effects of MCI/MI and MI were estimated by histology following 6- or 24-h exposure. Overall results show that MI in formulations or in aqueous standard solutions quickly permeated the skin with time lags less than 15 min while MCI was much slower (>3.5 h). MCI in formulations had permeation rates up to five times greater than that for MI in the same product, and in two tested creams were not found to permeate skin. Some signs of irritation were observed by histology; especially at the highest MCI/MI concentrations (750/250 µg/mL) in aqueous solutions. This confirms that MCI reacts readily with skin and may induce local irritation. The MCI and MI permeations are also greatly influenced by the topical vehicle. It is, therefore, more relevant to test exposures to formulations than aqueous standard solutions.

TREXMO: A Translation Tool to Support the Use of Regulatory Occupational Exposure Models.

Occupational exposure models vary significantly in their complexity, purpose, and the level of expertise required from the user. Different parameters in the same model may lead to different exposure estimates for the same exposure situation. This paper presents a tool developed to deal with this concern-TREXMO or TRanslation of EXposure MOdels. TREXMO integrates six commonly used occupational exposure models, namely, ART v.1.5, STOFFENMANAGER(®) v.5.1, ECETOC TRA v.3, MEASE v.1.02.01, EMKG-EXPO-TOOL, and EASE v.2.0. By enabling a semi-automatic translation between the parameters of these six models, TREXMO facilitates their simultaneous use. For a given exposure situation, defined by a set of parameters in one of the models, TREXMO provides the user with the most appropriate parameters to use in the other exposure models. Results showed that, once an exposure situation and parameters were set in ART, TREXMO reduced the number of possible outcomes in the other models by 1-4 orders of magnitude. The tool should manage to reduce the uncertain entry or selection of parameters in the six models, improve between-user reliability, and reduce the time required for running several models for a given exposure situation. In addition to these advantages, registrants of chemicals and authorities should benefit from more reliable exposure estimates for the risk characterization of dangerous chemicals under Regulation, Evaluation, Authorisation and restriction of CHemicals (REACH).

A Web-based Tool to Aid the Identification of Chemicals Potentially Posing a Health Risk through Percutaneous Exposure.

Occupational hygiene practitioners typically assess the risk posed by occupational exposure by comparing exposure measurements to regulatory occupational exposure limits (OELs). In most jurisdictions, OELs are only available for exposure by the inhalation pathway. Skin notations are used to indicate substances for which dermal exposure may lead to health effects. However, these notations are either present or absent and provide no indication of acceptable levels of exposure. Furthermore, the methodology and framework for assigning skin notation differ widely across jurisdictions resulting in inconsistencies in the substances that carry notations. The UPERCUT tool was developed in response to these limitations. It helps occupational health stakeholders to assess the hazard associated with dermal exposure to chemicals. UPERCUT integrates dermal quantitative structure-activity relationships (QSARs) and toxicological data to provide users with a skin hazard index called the dermal hazard ratio (DHR) for the substance and scenario of interest. The DHR is the ratio between the estimated 'received' dose and the 'acceptable' dose. The 'received' dose is estimated using physico-chemical data and information on the exposure scenario provided by the user (body parts exposure and exposure duration), and the 'acceptable' dose is estimated using inhalation OELs and toxicological data. The uncertainty surrounding the DHR is estimated with Monte Carlo simulation. Additional information on the selected substances includes intrinsic skin permeation potential of the substance and the existence of skin notations. UPERCUT is the only available tool that estimates the absorbed dose and compares this to an acceptable dose. In the absence of dermal OELs it provides a systematic and simple approach for screening dermal exposure scenarios for 1686 substances.

[Biomonitoring information management and communication: an ethical and interdisciplinary perspective]. / Gestion et communication de l'information en surveillance biologique. Une approche éthique et interdisciplinaire.

This study explores biomonitoring communication with workers exposed to risks. Using a qualitative approach, semi-directive interviews were performed. Results show that occupational physicians and workers share some perceptions, but also point out communication gaps. Consequently, informed consent is not guaranteed. This article proposes some recommendations for occupational physicians' practices.

Human leukocyte antigen class II variants and adult-onset asthma: does occupational allergen exposure play a role?

Recently, a locus centred on rs9273349 in the HLA-DQ region emerged from genome-wide association studies of adult-onset asthma. We aimed to further investigate the role of human leukocyte antigen (HLA) class II in adult-onset asthma and a possible interaction with occupational exposures. We imputed classical HLA-II alleles from 7579 single-nucleotide polymorphisms in 6025 subjects (1202 with adult-onset asthma) from European cohorts: ECRHS, SAPALDIA, EGEA and B58C, and from surveys of bakers and agricultural workers. Based on an asthma-specific job-exposure matrix, 2629 subjects had ever been exposed to high molecular weight (HMW) allergens. We explored associations between 23 common HLA-II alleles and adult-onset asthma, and tested for gene-environment interaction with occupational exposure to HMW allergens. Interaction was also tested for rs9273349. Marginal associations of classical HLA-II alleles and adult-onset asthma were not statistically significant. Interaction was detected between the DPB1*03:01 allele and exposure to HMW allergens (p = 0.009), in particular to latex (p = 0.01). In the unexposed group, the DPB1*03:01 allele was associated with adult-onset asthma (OR 0.67, 95%CI 0.53-0.86). HMW allergen exposures did not modify the association of rs9273349 with adult-onset asthma. Common classical HLA-II alleles were not marginally associated with adult-onset asthma. The association of latex exposure and adult-onset asthma may be modified by DPB1*03:01.

Human skin in vitro permeation of bentazon and isoproturon formulations with or without protective clothing suit.

Skin exposures to chemicals may lead, through percutaneous permeation, to a significant increase in systemic circulation. Skin is the primary route of entry during some occupational activities, especially in agriculture. To reduce skin exposures, the use of personal protective equipment (PPE) is recommended. PPE efficiency is characterized as the time until products permeate through material (lag time, Tlag). Both skin and PPE permeations are assessed using similar in vitro methods; the diffusion cell system. Flow-through diffusion cells were used in this study to assess the permeation of two herbicides, bentazon and isoproturon, as well as four related commercial formulations (Basagran(®), Basamais(®), Arelon(®) and Matara(®)). Permeation was measured through fresh excised human skin, protective clothing suits (suits) (Microchem(®) 3000, AgriSafe Pro(®), Proshield(®) and Microgard(®) 2000 Plus Green), and a combination of skin and suits. Both herbicides, tested by itself or as an active ingredient in formulations, permeated readily through human skin and tested suits (Tlag < 2 h). High permeation coefficients were obtained regardless of formulations or tested membranes, except for Microchem(®) 3000. Short Tlag, were observed even when skin was covered with suits, except for Microchem(®) 3000. Kp values tended to decrease when suits covered the skin (except when Arelon(®) was applied to skin covered with AgriSafe Pro and Microgard(®) 2000), suggesting that Tlag alone is insufficient in characterizing suits. To better estimate human skin permeations, in vitro experiments should not only use human skin but also consider the intended use of the suit, i.e., the active ingredient concentrations and type of formulations, which significantly affect skin permeation.

Airborne exposures to monoethanolamine, glycol ethers, and benzyl alcohol during professional cleaning: a pilot study.

UNLABELLED: A growing body of epidemiologic evidence suggests an association between exposure to cleaning products and respiratory dysfunction. Due to the lack of quantitative assessments of respiratory exposures to airborne irritants and sensitizers among professional cleaners, the culpable substances have yet to be identified. PURPOSE: Focusing on previously identified irritants, our aims were to determine (i) airborne concentrations of monoethanolamine (MEA), glycol ethers, and benzyl alcohol (BA) during different cleaning tasks performed by professional cleaning workers and assess their determinants; and (ii) air concentrations of formaldehyde, a known indoor air contaminant. METHODS: Personal air samples were collected in 12 cleaning companies, and analyzed by conventional methods. RESULTS: Nearly all air concentrations [MEA (n = 68), glycol ethers (n = 79), BA (n = 15), and formaldehyde (n = 45)] were far below (<1/10) of the corresponding Swiss occupational exposure limits (OEL), except for ethylene glycol mono-n-butyl ether (EGBE). For butoxypropanol and BA, no OELs exist. Although only detected once, EGBE air concentrations (n = 4) were high (49.48-58.72mg m(-3)), and close to the Swiss OEL (49mg m(-3)). When substances were not noted as present in safety data sheets of cleaning products used but were measured, air concentrations showed no presence of MEA, while the glycol ethers were often present, and formaldehyde was universally detected. Exposure to MEA was affected by its amount used (P = 0.036), and spraying (P = 0.000) and exposure to butoxypropanol was affected by spraying (P = 0.007) and cross-ventilation (P = 0.000). CONCLUSIONS: Professional cleaners were found to be exposed to multiple airborne irritants at low concentrations, thus these substances should be considered in investigations of respiratory dysfunctions in the cleaning industry; especially in specialized cleaning tasks such as intensive floor cleaning.

Hazardous substances in frequently used professional cleaning products.

BACKGROUND: A growing number of studies have identified cleaners as a group at risk for adverse health effects of the skin and the respiratory tract. Chemical substances present in cleaning products could be responsible for these effects. Currently, only limited information is available about irritant and health hazardous chemical substances found in cleaning products. We hypothesized that chemical substances present in cleaning products are known health hazardous substances that might be involved in adverse health effects of the skin and the respiratory tract. METHODS: We performed a systematic review of cleaning products used in the Swiss cleaning sector. We surveyed Swiss professional cleaning companies (n = 1476) to identify the most used products (n = 105) for inclusion. Safety data sheets (SDSs) were reviewed and hazardous substances present in cleaning products were tabulated with current European and global harmonized system hazard labels. RESULTS: Professional cleaning products are mixtures of substances (arithmetic mean 3.5 +/- 2.8), and more than 132 different chemical substances were identified in 105 products. The main groups of chemicals were fragrances, glycol ethers, surfactants, solvents; and to a lesser extent, phosphates, salts, detergents, pH-stabilizers, acids, and bases. Up to 75% of products contained irritant (Xi), 64% harmful (Xn) and 28% corrosive (C) labeled substances. Hazards for eyes (59%) and skin (50%), and hazards by ingestion (60%) were the most reported. CONCLUSIONS: Cleaning products potentially give rise to simultaneous exposures to different chemical substances. As professional cleaners represent a large workforce, and cleaning products are widely used, it is a major public health issue to better understand these exposures. The list of substances provided in this study contains important information for future occupational exposure assessment studies.

Sex differences in urinary levels of several biological indicators of exposure: a simulation study using a compartmental-based toxicokinetic model.

Toxicokinetic modeling is a useful tool to describe or predict the behavior of a chemical agent in the human or animal organism. A general model based on four compartments was developed in a previous study to quantify the effect of human variability on a wide range of biological exposure indicators. The aim of this study was to adapt this existing general toxicokinetic model to three organic solvents--methyl ethyl ketone, 1-methoxy-2-propanol, and 1,1,1,-trichloroethane--and to take into account sex differences. In a previous human volunteer study we assessed the impact of sex on different biomarkers of exposure corresponding to the three organic solvents mentioned above. Results from that study suggested that not only physiological differences between men and women but also differences due to sex hormones levels could influence the toxicokinetics of the solvents. In fact the use of hormonal contraceptive had an effect on the urinary levels of several biomarkers, suggesting that exogenous sex hormones could influence CYP2E1 enzyme activity. These experimental data were used to calibrate the toxicokinetic models developed in this study. Our results showed that it was possible to use an existing general toxicokinetic model for other compounds. In fact, most of the simulation results showed good agreement with the experimental data obtained for the studied solvents, with a percentage of model predictions that lies within the 95% confidence interval varying from 44.4 to 90%. Results pointed out that for same exposure conditions, men and women can show important differences in urinary levels of biological indicators of exposure. Moreover, when running the models by simulating industrial working conditions, these differences could be even more pronounced. A general and simple toxicokinetic model, adapted for three well-known organic solvents, allowed us to show that metabolic parameters can have an important impact on the urinary levels of the corresponding biomarkers. These observations give evidence of an interindividual variability, an aspect that should have its place in the approaches for setting limits of occupational exposure.

A model of ocular ambient irradiance at any head orientation.

Exposure to ambient ultraviolet radiation is associated with various ocular pathologies. Estimating the irradiance received by the eyes is therefore essential from a preventive perspective and to study the relationship between light exposure and eye diseases. However, measuring ambient irradiance on the ocular surface is challenging. Current methods are either approximations or rely on simplified setups. Additionally, factors like head rotation further complicate measurements for prolonged exposures. This study proposes a novel numerical approach to address this issue by developing an analytical model for calculating irradiance received by the eye and surrounding ocular area. The model takes into account local ambient irradiance, sun position, and head orientation. It offers a versatile and cost-effective means of calculating ocular irradiance, adaptable to diverse scenarios, and serves both as a predictive tool and as a way to compute correction factors, such as the fraction of diffuse irradiance received by the eyes. Furthermore, it can be tailored for prolonged durations, facilitating the calculation of radiant dose obtained during extended exposures.

A numerical model for quantifying exposure to natural and artificial light in human health research.

Various skin and ocular pathologies can result from overexposure to ultraviolet radiation and blue light. Assessing the potential harm of exposure to these light sources requires quantifying the energy received to specific target tissue. Despite a well-established understanding of the light-disease relationship, the quantification of received energy in diverse lighting scenarios proves challenging due to the multitude of light sources and continuous variation in the orientation of receiving tissues (skin and eyes). This complexity makes the determination of health hazards associated with specific lighting conditions difficult. In this study, we present a solution to this challenge using a numerical approach. Through the implementation of algorithms applied to 3D geometries, we created and validated a numerical model that simulates skin and ocular exposure to both natural and artificial light sources. The resulting numerical model is a computational framework in which customizable exposure scenarios can be implemented. The ability to adapt simulations to different configurations for study makes this model a potential investigative method in human health research.

Polychlorinated dibenzo-p-dioxins (PCDDs) and dibenzofurans (PCDFs) soil contamination in Lausanne, Switzerland: Combining pollution mapping and human exposure assessment for targeted risk management.

In December 2020, high soil concentrations of polychlorinated dibenzo-p-dioxins (PCDDs) and dibenzofurans (PCDFs) were discovered across large parts of Lausanne, Switzerland. Concentrations reached up to 640 ng TEQWHO-2005/kg dry weight. The most likely source was a former municipal waste incinerator. A three-step, multidisciplinary approach to human health risk assessment was conducted to determine the potential population exposure to PCDD/Fs and identify appropriate preventive measures. First, exposure scenarios were developed based on contaminated land uses. Second, the toxicological risks of different scenarios were evaluated using a toxicokinetic model estimating increases in blood serum PCDD/F concentrations over background concentrations from the general population's food consumption. Third, a detailed geostatistical mapping of PCDD/F soil contamination was performed. Stochastic simulations with an external drift and an anisotropic model of the variogram were generated to incorporate the effects of distance from emission source, topography, and main wind directions on the spatial distribution of PCDD/Fs in topsoil. Three main scenarios were assessed: i) direct ingestion of soil by children in playgrounds; ii) consumption of vegetables from private gardens by children and adults; and iii) consumption of food from livestock and poultry raised on contaminated soil. The worst exposure scenario involved the consumption of eggs from private hen houses, resulting in PCDD/F concentrations in serum an order of magnitude higher than might normally be expected. No relevant increases in serum concentrations were calculated for direct soil ingestion and vegetable consumption, except for cucurbitaceous vegetables. Combining mapping and exposure scenario assessment resulted in targeted protective measures for land users, especially concerning food consumption. The results also raised concerns about the potential unsafe consumption of products derived from animals raised on land with PCDD/F concentrations only moderately over environmental background levels.

A simple gas chromatography method for the analysis of monoethanolamine in air.

A simple method determining airborne monoethanolamine has been developed. Monoethanolamine determination has traditionally been difficult due to analytical separation problems. Even in recent sophisticated methods, this difficulty remains as the major issue often resulting in time-consuming sample preparations. Impregnated glass fiber filters were used for sampling. Desorption of monoethanolamine was followed by capillary GC analysis and nitrogen phosphorous selective detection. Separation was achieved using a specific column for monoethanolamines (35% diphenyl and 65% dimethyl polysiloxane). The internal standard was quinoline. Derivatization steps were not needed. The calibration range was 0.5-80 µg/mL with a good correlation (R(2) = 0.996). Averaged overall precisions and accuracies were 4.8% and -7.8% for intraday (n = 30), and 10.5% and -5.9% for interday (n = 72). Mean recovery from spiked filters was 92.8% for the intraday variation, and 94.1% for the interday variation. Monoethanolamine on stored spiked filters was stable for at least 4 weeks at 5°C. This newly developed method was used among professional cleaners and air concentrations (n = 4) were 0.42 and 0.17 mg/m(3) for personal and 0.23 and 0.43 mg/m(3) for stationary measurements. The monoethanolamine air concentration method described here was simple, sensitive, and convenient both in terms of sampling and analytical analysis.