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The paper presents the application potential of untreated/treated woven/non-woven coir geotextile in the unpaved roads. The chemical used for the treatment of the coir geotextiles were p-aminopheno...

Morpholine is a common chemical used as emulsifier in the preparation of wax coatings for some fruit to help them remain fresh and protect against insects and fungal contamination. It has been reported that morpholine has acute toxic effects on rodents. In the present study, morpholine concentrations were analysed in fruits (citrus fruits, apples, strawberries and grapes) and juices (apple juice and orange juice) in order to determine dietary exposure among the Chinese population. A total of 732 fruit and juice samples were collected during 2015-2016, which covered major foods in China. Fruit and juice consumption data were taken from China National Nutrient and Health Survey (2002) and include data from 16,407 fruit or juice consumers. It was found that mean dietary exposure to morpholine residues from fruits and/or juices for general Chinese consumers and children 2-6 years old were 0.42 and 1.24 µg/kg bw/day, respectively. The 97.5% intake in general Chinese consumers and children 2-6 years old were 2.25 and 6.90 µg/kg bw/day, respectively. The primary food sources of the morpholine dietary intake of general Chinese consumers were citrus fruits (57.4%) and apples (40.8%). These findings suggested that dietary exposure to morpholine in the Chinese population was lower than the acceptable daily intake of morpholine, and there are no health concerns.

Triclosan (TCS), a chemical used for its antibacterial properties, is an ingredient in many detergents, soaps, deodorants, cosmetics, antimicrobial creams, toothpastes, and an additive in various plastics and textiles. The behavioral changes at different TCS concentrations (0.001–0.002–0.005–0.01–0.02–0.05–0.1–0.2–0.5 mg/L) were determined for the each test organisms in the study. The synthetic freshwater has temperature 20 ± 2°C, dissolved oxygen 7.0 ± 2 mg/L, pH 7.0–8.0. All experiments were replicated three times, in 14 h light, 10 h dark incubations, 10 fishes were put to each aquarium. In hourly and daily observations, times of dead and number for Poecilia reticulata, Danio rerio were recorded. Behavioral changes of Poecilia reticulata and Danio rerio were observed, such as fast-moving, uncontrolled swimming, trying to escape out of the water, vertical action to the water surface, loss of balance, respiratory difficulties, chills, and inversion. © 2018 Taylor & Francis Group, LLC.

Melamine is a synthetic chemical used in the manufacture of resins, pigments, and superplasticizers. Human beings can be exposed to melamine through various sources such as migration from related products into foods, pesticide contamination, and illegal addition to foods. Toxicity studies suggest that prolonged consumption of melamine could lead to the formation of kidney stones or even death. Therefore, reliable and accurate detection methods are essential to prevent human exposure to melamine. Sample preparation is of critical importance, since it could directly affect the performance of analytical methods. Some methods for the detection of melamine include instrumental analysis, immunoassays, and sensor methods. In this paper, we have summarized the state-of-the-art methods used for food sample preparation as well as the various detection techniques available for melamine. Combinations of multiple techniques and new materials used in the detection of melamine have also been reviewed. Finally, future perspectives on the applications of microfluidic devices have also been provided.

Bisphenol A is a chemical used to make certain types of plastics and is found in numerous consumer products. Because scientific studies have raised concerns about Bisphenol A’s potential impact on human health, it has been removed from some (but not all) products. What many consumers do not know, however, is that Bisphenol A is often replaced with other, less-studied chemicals whose health implications are virtually unknown. This type of situation is known as a potential ‘regrettable substitution’, because the substitute material might actually be worse than the material that it replaces. Regrettable substitutions are a common concern among policymakers, and they are a real-world manifestation of the tension that can exist between the desire to avoid risk (known possible consequences that might or might not occur) and ambiguity (second-order uncertainty), which is itself aversive. In this article we examine how people make such trade-offs using the example of Bisphenol A. Using data from Study 1, we show that people have inconsistent preferences toward these alternatives and that choice is largely determined by irrelevant contextual factors such as the order in which the alternatives are evaluated. Using data from Study 2 we further demonstrate that when people are informed of the presence of substitute chemicals, labeling the alternative product as ‘free’ of Bisphenol A causes them to be significantly more likely to choose the alternative despite its ambiguity. We discuss the relevance of these findings for extant psychological theories as well as their implications for risk, policy and health communication.

Recently, worker exposures to diacetyl, a chemical used in the production of butter popcorn, has been linked to bronchiolitis obliterans, a severe lung disease. This chemical is also used in the flavor industry to confer a buttery flavor to many food products, with more than 228,000 pounds used in 2005. Diacetyl exposures were monitored at 16 small-to medium-sized flavor facilities to determine potential diacetyl exposures. A total of 181 diacetyl samples (both personal and area samples) were obtained, and a number of real-time samples were collected using an IR spectrometer. Samples were obtained during liquid and powder compounding operations at the facilities as well as during laboratory and QC operations. The personal and area samples ranged from non-detectable (0.02 ppm) to as high as 60 ppm. Ninety-two (51%) of the samples were below the limit of detection, and the mean diacetyl concentration for all processes was 1.80 ppm. Mean diacetyl levels during powder operations were generally higher (4.24 ppm) than mean diacetyl levels during liquid operations (2.02 ppm). Maximum real-time diacetyl exposures during powder operations could reach as high as 525 ppm. These results are similar to exposures measured by NIOSH in popcorn facilities where lung disease was found; however, the duration of use and frequency of use may be significantly lower.

Bisphenol A (BPA, CAS RN 80-05-7) is a high production volume chemical used as an intermediate in the production of polycarbonate plastic and epoxy resins. During its manufacture and use, some emissions to surface waters are anticipated. Chronic predicted no effect concentrations (PNECs) for aquatic systems are used to support the assessment of potential risks to aquatic organisms in receiving waters. PNECs for a compound are considered protective of populations, communities, and ecosystems. Traditionally, PNECs are derived by taking the lowest no-observed effect concentration (NOEC) from a set of toxicity studies and dividing by an assessment factor (e.g., 10 to 1000). This traditional approach is appropriate for substances with few data, but may not be necessary for substances with many valid studies. For well-studied substances, statistical approaches (i.e., development of Species Sensitivity Distribution or SSD methods) can be used to calculate a PNEC that makes use of the full distribution o...

Ground and surface water contamination by perchlorate, a non-biodegradable chemical used in rocket fuel and military ammunition, has stimulated increasing concern in the United States. The regulatory and risk issues associated with perchlorate have been complicated by the geographical extent of its distribution, its properties as an endocrine disruptor and the uncertainty surrounding its possible risks. The risk politics behind perchlorate contamination in areas of southern California, and the changing levels of perceived and acceptable risk posed by the related risk assessment process are considered. By examining the nature of the scientific research and rationality framing in the debate, the contradictions of precaution in scientific methodologies and regulation, and the possible socio-economic consequences of technical framing, are highlighted.

Hematoxylin is a naturally occurring chemical used as the basis of a dye in laboratories throughout the world to stain nuclei in microscope slide preparations. This chemical is extracted from the logwood tree Hematoxylon campechianum and was discovered by Spanish explorers to the Yucatan in 1502. A vigorous trade soon developed related to growing and preparing hematoxylin for use in dyeing fabrics in Europe. In the mid 1800s, amateur microscopists first used hematoxylin to stain cellular components. Later scientists developed a wide range of techniques to demonstrate different cellular components. Hematoxylin remains the most popular nuclear stain in histology. This paper briefly describes the history of hematoxylin production and use in histology.

Silver stains are commonly used in histology laboratories to demonstrate a variety of tissue substances. With the passage of time. it has become evident that several of the chemicals used in silver stains, as well as silver compounds themselves, pose hazards to laboratory workers. Disposal of these chemicals also poses a problem.This article briefly outlines some of the hazards of working with the chemicals used in silver stains. A comprehensive chemical hygiene plan, which must be developed for each laboratory, provides a standard operating procedure for working safely with chemicals. Material safety data sheets provide information on each chemical used in the laboratory and must be available. The use of several of the chemicals employed in silver stains is covered by Federal, state, and local laws. The state and local laws may be more stringent than the Federal laws. (The J Histotechnol 19:197, 1996)