Naturally occurring chemicals health hazards

Approach to dealing with naturally occurring chemicals Aesthetic effects Common health hazards... 

Chemical hazards also pose a concern for winemakers. These can be divided into naturally occurring, intentionally added, and unintentional/ incidental. Examples of naturally occurring chemicals that could pose a risk to human health are biogenic amines (Section 11.3.6), ethyl carbamate (11.3.2), and mycotoxins (Section 4.5.2). Intentionally added chemicals include sulfur dioxide (gas, sulfur wicks, or potassium metabisulfite), tartaric acid, Velcorin (Section 5.2.2), and microbial nutrient formulations (diammonium phosphate or proprietary blends). Finally, uninten-tional/incidental chemicals would include residues of agricultural chemicals that exceed approved levels, cleaners or sanitizers (Chapter 9), and the inadvertent transfer of lubricants from equipment. 

Radioactive substances (radionuclides) are known health hazards that emit energetic waves and/or particles that can cause both carcinogenic and noncarcinogenic health effects. Radionuclides pose unique threats to source water supplies and chemical processing, storage, or distribution systems because radiation emitted from radionuclides in chemical or industrial waste systems can affect individuals through several pathways by direct contact with, ingestion or inhalation of, or external exposure to, the contaminated waste stream. While radiation can occur naturally in some cases due to the decay of some minerals, intentional and nonintentional releases of... 

Asbestos constitutes several types of hydrated silicate mineral fibers. The types of asbestos, their chemical compositions, and CAS Numbers are presented in Table 3.8.1. These substances occur in nature in rocks, silicate minerals, fibrous stones, and underground mines. This class of substances exhibits unique properties of noncombustibility, high resistance to acids, and high tensile strength for which they were widely used in many products, including floor and roofing tiles, cement, textiles, ropes, wallboards, and papers. Because of the health hazards associated with excessive exposure to asbestos, the use of these substances is currently banned. 

The development of chemical industry has provided us with the means to produce, on an ecologically significant scale, chemicals that interfere with the natural cycles of synthesis and breakdown either because they accelerate or slow down large-scale natural processes (e.g., the fluoro chloro hydrocarbons which accelerate the breakdown of ozone by sunlight) or, more commonly, because they resist breakdown themselves (e.g., certain synthetic polymers). This has become a matter of grave and widespread concern and has resulted in regulations and voluntary measures to restrict or prohibit the manufacture and use of materials that interfere with the natural cycles. This concern is particularly acute in those cases where this interference has direct or indirect adverse effects upon human health (as in the case of the fluoro chloro hydrocarbons), but it exists also where massive accumulation occurs without known health hazards (as in the case of the too-stable synthetic polymers). 

Microbial hazards make the largest contribution to waterborne disease in developed and developing countries, Nevertheless, chemicals in water supplies can cause serious health problems - whether the chemicals are naturally occurring or derive from sources of pollution. At a global scale, fluoride and arsenic are the most significant chemicals, each affecting perhaps millions of people, However, many other chemicals can be important contaminants of drinking-water under specific local conditions. 

In any case, the darkening reaction doesn t pose a health hazard. Even if your potatoes have turned black, you can still eat them. After all, potatoes are a true comfort food. Due to their high carbohydrate content, they elevate serotonin levels in the brain, which has a calming effect. And, believe it or not, researchers have discovered that potatoes harbor small amounts of naturally occurring benzodiazepines, compounds in the same chemical family as Valium. So, go ahead and enjoy your Christmas pudding, white or black. 

There are also naturally occurring fibrous silicate minerals. The most commercially important of these today is Wollastonite. It has the chemical formula CaSiOj. Wollastonite particles are shown in Fig. 1.16. Asbestos, now largely banned as a health hazard, is also a fibrous silicate. Wollastonite is obtained by mining or reaction between calcite and silica at temperatures higher than 450 °C ... 

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