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The purpose of this paper is to explore inhalation levels and dermal exposure to toluene among printing workers who wore no personal protective equipment; it is conducted in a plastic bag factory. Using a charcoal cloth pad (CCP) as a dermal sampler to assess skin permeation of liquid toluene is also investigated.

In total, 27 stationary air samples as well as urine and dermal samples were collected over 9 days from 11 printing workers. Six pieces of CCP were wrapped on each of the workers’ fingers for the dermal sample collection. Air samples were collected and analyzed according to NIOSH No. 1501, and 65 post-shift urine samples were collected and analyzed using gas chromatography equipped with headspace sampler (GC-HS/FID). Multiple linear regression was employed to analyze the association between the studied variables.

The mean (SD) urinary toluene (UTol) level was 13.42 (9.72) ug/L. Toluene on the CCP (TolCCP) was a meaningful predictor for UTol (p-value=0.027) with r and r² values of 0.441 and 0.195, respectively. The r and r² of the model using the toluene time-weighted average concentrations in air were 0.739 and 0.546, respectively. The absorbed dose of toluene determined from the TolCCP ranged from 1.05 to 91.94 mg, accounting for 12.3 percent of the threshold limit value (TLV).

Dermal exposure was insignificant when workers wore respirators, but when not, dermal absorption could contribute to the overall uptake and exposure above the TLV. Appropriate gloves should be assigned to the workers to reduce dermal exposure to toluene.

The purpose of this paper is to present a numerical analysis of the laser surgery of port wine stain (PWS) with cryogen spray cooling to compare the treatment effect between pulse dye laser and Nd:YAG laser, explain the incomplete clear of the lesion and optimize the laser parameter.

The complex structure of skin and PWS is simplified to a multi-layer skin model that consists of top epidermal layer and underneath dermis layer embedded with discrete blood vessels. The cooling effect of cryogen spray before laser firing is quantified by a general correlation obtained recently from the experimental data. The light distribution is modeled by the Monte Carlo method. The heat transfer in skin tissue is calculated by Pennes bioheat transfer model. The thermal damage of blood vessel is quantified by the Arrhenius damage integral.

For the vessel size studied (10-120 µm), pulse duration is recommended shorter than 6 ms. Large and deeply buried vessels, which may survive from 595 nm laser irradiation, can be coagulated by 1,064 nm laser due to its deep light penetration depth in skin. Furthermore, a desired uniform heating within the large vessel lumen can be achieved by 1,064 nm laser whereas 595 nm laser produce non-uniform heating.

The possible reason for the poor responding and incomplete clearance lesions is clarified. Laser wavelength and pulse duration are suggested to improve the clinical results.

IT IS THE practice among some large users of ‘soluble’ cutting oils, such as motor manufacturers, to issue specifications imposing pH limitations on the oil in emulsion form. Although the limits fixed may vary widely among different users, the reasons for the particular level chosen are identical and invariably originate from the company medical department through their efforts to control factors likely to contribute to occupational dermatoses.

Live non-invasive monitoring of biomarkers is of great importance for the medical community. Moreover, some studies suggest that there is a substantial business gap in the development of mass-production commercial sweat-analysing wearables with great revenue potential. The objective of this work is to quantify the concentration of biomarkers that reaches the area of the garment where a sensor is positioned to advance the development of commercial sweat-analysing garments.

Computational analysis of the microfluidic transport of biomarkers within eccrine sweat glands provides a powerful way to explore the potential for quantitative measurements of biomarkers that can be related to the health and/or the physical activity parameters of an individual. The numerical modelling of sweat glands and the interaction of sweat with a textile layer remain however rather unexplored. This work presents a simulation of the production of sweat in the eccrine gland, reabsorption from the dermal duct into the surrounding skin and diffusion within an overlying garment.

The model represents satisfactorily the relationship between the biomarker concentration and the flow rate of sweat. The biomarker distribution across an overlying garment has also been calculated and subsequently compared to the minimum amount detectable by a sensor previously reported in the literature. The model can thus be utilized to check whether or not a given sensor can detect the minimum biomarker concentration threshold accumulated on a particular type of garment.

The present work presents to the best of our knowledge, the earliest numerical models of the sweat gland carried out so far. The model describes the flow of human sweat along the sweat duct and on to an overlying piece of garment. The model considers complex phenomena, such as reabsorption of sweat into the skin layers surrounding the duct, and the structure of the fibres composing the garment. Biomarker concentration maps are obtained to check whether sensors can detect the threshold concentration that triggers an electric signal. This model finds application in the development of smart textiles.

The purpose of this paper is to provide a method for determining the numerical solutions of the thermal damage of cylindrical living tissues using hyperbolic bioheat model. Due to the complex governing equation, the finite element approach has been adopted to solve these problems. To approve the accuracy of the numerical solution, the numerical outcomes obtained by the finite element approach are compared with the existing experimental study. In addition, the comparisons between the numerical outcomes and the existing experimental data displays that the present mathematical models are efficient tools to evaluate the bioheat transfer in the cylindrical living tissue. Numerical computations for temperatures and thermal damage are presented graphically.

In this section, the complex equation of bioheat transfer based upon one relaxation time in cylindrical living tissue is summarized by using the finite element method. This method has been used here to get the solution of equation (8) with initial conditions (9) and boundary conditions (10). The finite element technique is a strong method originally advanced for numerical solutions of complex problems in many fields, and it is the approach of choice for complex systems. Another advantage of this method is that it makes it possible to visualize and quantify the physical effects independently of the experimental limits. Abbas and his colleagues [26-34] have solved several problems under generalized thermoelastic theories.

In this study, the different values of blood perfusion and thermal relaxation time of the dermal part of cylindrical living tissue are used. To verify the accuracy of the numerical solutions, the numerical outcomes obtained by the finite element procedure and the existing experimental study have been compared. This comparison displays that the present mathematical model is an effective tool to evaluate the bioheat transfer in the living tissue.

The validation of the obtained results by using experimental data the numerical solution of hyperbolic bioheat equation is presented. Due to the nonlinearity of the basic equation, the finite element approach is adopted. The effects of thermal relaxation times on the thermal damage and temperature are studied.

This study aims to prepare low-cost biomaterials from renewable natural resources (rosin).

Preparation of different biomaterials, ethylene glycol maleic rosin (EGMR), glycerol maleic rosin, pentaerythritol maleic rosin and sorbitol maleic rosin (SMR) esters, then evaluated by stability studies, moisture absorption, swelling index parameters, thermogravimetric analysis and skin irritation studies.

The prepared rosin derivatives had excellent moisture safety, according to the results. From EGMR to SMR, the swelling indices increase.

These rosin biomaterials were used in coating, especially in the field of pharmaceutical coating, and good results were obtained in this study.

As these biomaterials rosin derivatives have excellent moisture resistance, they are recommended for use as coating materials for moisture-sensitive drugs.

There has recently been a lot of interest in researching the effects of rosin derivatives in various drug delivery systems.

The safety of operators handling pesticides is still one of the main problems facing Thai agricultural workers. The purpose of this paper is to study the safety of farmers and the techniques recommended to farmers by the Department of Agriculture in Thailand, i.e. spraying to achieve optimum spray volume with consideration for wind direction – henceforth referred to as officer techniques.

Operator exposure was detected by verifying the deposition of dye tracer on the coveralls worn by ten spray service team leaders, for all applications between May and June 2017. For each technique, a total of 15 patches were attached at the lower legs, thigh, chest, forearms, upper arms, hands, face, forehead and back. Each individual technique was performed four times in the area of 1,800 m².

The results showed that the deposits with the farmers’ techniques was much higher than with officers’ techniques ranging from 2.32 to 23.91 times at the tillering stage and 9.90 to 56.79 times at the booting stage, respectively. These results indicate that the spray application technique has a considerable potential for reducing the contamination of spray operators by 56.96–98.23 percent. Operator safety can be considerably improved by the spray application technique employed. Without any investment and changing equipment, only by considering wind direction, officers’ techniques could avoid much deposition, which is the most practical operation in the field. The boom sprayer as a novel recommended technique is an alternative giving a positive result and it can be a substitute for the conventional method. Furthermore, the authors must pay attention to personal protective equipment (PPE) because depositions were discovered on the whole of the bodies of those tested. PPE is the best way to protect an operator from pesticide contamination.

Operator exposure data can be helpful in further development of exposure models and databases for risk assessment and pesticide registration in Thailand.

Children living in agricultural areas are exposed to pesticides in their living areas and through activities of daily living. These exposures may lead to adverse health effects. The purpose of this paper is to investigate household environmental and behavioural factors associated with chlorpyrifos exposure and resultant adverse health effects in children living in an agricultural community.

A cross-sectional study was conducted including 65 toddlers (age of 12–36 months) and their parents were face-to-face interviewed from January to February 2016. Toddler’s hands and feet, toys and floors were wiped for chlorpyrifos residue analysis. The wipes were extracted and analysed by gas chromatography with a flame photometric detector, and blood cholinesterase activity was measured by the EQM Test-mate (model 400).

The average age (± standard deviation) of children was 19.9 (±5.9) months. Chlorpyrifos detections were 61.5 per cent (hands), 57.1 per cent (toys), 53.8 per cent (floors) and 30.8 per cent (feet). The highest chlorpyrifos residue concentration was detected on toy surface (3.022 µg/m²). Chlorpyrifos residues on hands and feet were positively correlated with concentrations on floors and toys (Spearman’s ρ, p<0.01). Multiple linear regression analysis revealed that more frequent hand washing (β=−0.236, p=0.067) and showering (β=−0.240, p=0.056) was negatively associated with chlorpyrifos residue on children’s body. House cleaning frequency was significantly associated with an increase in haemoglobin-adjusted erythrocyte cholinesterase (β=0.251, p<0.05).

Chlorpyrifos exposures found in the children household area through their activities and behaviours can cause several adverse health effects. The circumstances associated with chlorpyrifos exposure should be mitigated and reduced to improve the household environment of children living agricultural areas.

The purpose of this article is to investigate the labor and environmental risks that exist in potato crops in an agricultural area of Colombia and to propose good labor and environmental welfare practices.

The study was conducted through the combination of quantitative and qualitative research approaches, applying pragmatic techniques and tools such as direct observation by field journal, questionnaire survey, checklist of working conditions and a specific methodology for the risk assessment.

It is identified that the production practices carried out by the cultivators studied are rudimentary, that the agrochemicals used affect the health and safety of the farmers and their families, constituting high-risk products for people and the environment. On the other hand, it is established that the training and qualification of workers is low, they do not use protection elements, or they are not adequate, representing a considerable degree of vulnerability.

With the findings of this research it is expected to improve the working conditions of potato growers and sustainability of agricultural processes in the area, whose results will also be very useful for the analysis of the issue throughout the agricultural sector in general, at a national or international level. Contributing in the same way to the fulfillment of the goals of the sustainable development goals.

The study purposes were to investigate the knowledge, attitude and practice of pesticide use and to determine the levels of serum cholinesterase among rice farmers in Nakhon Nayok province, Thailand.

A cross-sectional study was carried out in communities in Nakhon Nayok Province, Thailand. Multistage random sampling was employed, selecting one person per each rice farmer household. Data was collected from 188 rice farmers using a structured face-to-face interview questionnaire. A reactive-paper finger-blood test was used to determine SChE levels. Chi-square test was used to determine the relationship between the practice of pesticide use and SChE levels.

The results indicated that the rice farmers had a fairly good knowledge and a neutral attitude toward the practice of pesticide use. Most of the respondents had a fairly proper practice of pesticide use. However, serum cholinesterase levels of the farmers were unsafe and risky. It signified that 68.1% of the farmers had a health risk from using pesticides. The prevalence of abnormal SChE levels among rice farmers with improper use was significantly higher than that among rice farmers who had a proper use.

The result provided a guideline for operational planning and control and prevention of health effects from pesticides use in farmers or other agriculturists who use pesticides in cultivation.

Concerned local agencies especially health-related agencies are able to conduct a training to educate and build safety awareness including monitoring continuously the safety behaviors toward pesticides use. It can be implemented by establishing leaders from health promoting hospitals led by village health volunteers, community leaders and participation from farmers to collaboratively monitor proper use of pesticides beginning with health surveillance in the abnormal SChE group to be screened for pesticide exposure every six months or one year.

Farmers gained knowledge and understanding of pesticides use and used it properly, which resulted in a reduction of pesticide residues in body as well as in the environment. In addition, the government policy should legislate measures for related agencies to promote proper use of pesticides. For instance, Department of Agriculture, Minister of Agriculture and Cooperatives should regularly supervise, monitor and inspect the production and distribution of pesticides in local shops and also systematically encourage agriculturists to adopt using pesticides that are less harmful.

Having knowledge, understanding and proper practices toward pesticides use, farmers can reduce health effects of pesticides use in themselves and family members.