Titanium Dioxide: Toxic or Safe?Written by Lori Stryker
Titanium dioxide is subject of new controversy, yet it is a substance as old as earth itself. It is one of top fifty chemicals produced worldwide. It is a white, opaque and naturally- occurring mineral found in two main forms: rutile and anatase. Both forms contain pure titanium dioxide that is bound to impurities. Titanium dioxide is chemically processed to remove these impurities, leaving pure, white pigment available for use. Titanium dioxide has a variety of uses, as it is odorless and absorbent. This mineral can be found in many products, ranging from paint to food to cosmetics. In cosmetics, it serves several purposes. It is a white pigment, an opacifier and a sunscreen. Concern has arisen from studies that have pointed to titanium dioxide as a carcinogen and photocatalyst, thus creating fear in consumers. But are these claims true? What does research on these allegations bear out? Would we as consumers benefit from avoiding this mineral to preserve our long-term health?A carcinogen is a substance that causes a cellular malfunction, causing cell to become cancerous and thus potentially lethal to surrounding tissue and ultimately body as these rapidly growing mutated cells take over. With surge in cancer rates among all segments of population, many people are attempting to reduce or eliminate their exposure to carcinogens. Titanium dioxide is regarded as an inert, non-toxic substance by many regulatory bodies such as MSDS (Material Safety Data Sheets) and others charged with responsibility of safeguarding health of occupational workers and public health. The MSDS states that titanium dioxide can cause some lung fibrosis at fifty times nuisance dust, defined by US Department of Labor as 15 mg/m cubed (OSHA) or 10 mg/m cubed (ACGIH Threshold Limit Value). The ACGIH states that titanium dioxide is "not classifiable as a human carcinogen". Symptoms of chronic overexposure to titanium dioxide in an industrial setting, according to MSDS, include a "slight increase in lung tumour incidence in lab rats". It also states "when titanium dioxide was fed to rats/mice in a carcinogen bioassay, it was not carcinogenic". The NIOSH declares that at 5000 mg/m cubed there was slight lung fibrosis, concluding that this substance was carcinogenic in rats. The NIOSH declaration of carcinogenicity in rats is based on a study by Lee, Trochimowicz & Reinhardt, "Pulmonary Response of Rats Exposed to Titanium Dioxide by Inhalation for Two Years" (1985). The authors of this study found that rats chronically exposed to excessive dust loading of 250 mg/m cubed and impaired clearance mechanisms within rat, for six hours per day, five days per week for two years, developed slight lung tumours. They also noted that biological relevance of this data to lung tumours in humans is negligible. It is important to note that rats are known to be an extremely sensitive species for developing tumours in lungs when overloaded with poorly soluble, low toxicity dust particles. Rat lungs process particles very differently compared to larger mammals such as dogs, primates or humans (Warheit, 2004). This sensitivity in lungs has not been observed in other rodent species such as mice or hamsters (Warheit, 2004), therefore using rat model to determine carcinogenicity of titanium dioxide in humans can be misleading, as extrapolation of species-specific data to humans is erroneous. Many organizations and businesses have perpetuated this assessment of carcinogenicity of titanium dioxide (ewg.org). However, several studies and study reviews have been used to compile safety disclaimers for regulations on permitted use of titanium dioxide. One such study review took place in Rome, 1969 between World Health Organization and Food & Agriculture Organization of United Nations. Cross species analyses were performed and reviewed for possible toxicity of titanium dioxide. The conference concluded that among following species: rats, dogs, guinea pigs, rabbits, cats and human males, ingestion of titanium dioxide at varying diet percentages and over long periods of time did not cause absorption of this mineral. Titanium dioxide particulates were not detected in blood, liver, kidney or urine and no adverse effects were noted from its ingestion. The U.S. Food & Drug Administration (2002) allows for its ingestion, external application including eye area, and considers it a safe substance for public health. Other epidemiological studies showed that workers exposed to titanium dioxide exhibited no statistically significant relationship between such exposure with lung cancer and respiratory disease, although some cases of pulmonary fibrosis did occur. These studies were conducted in industrial settings where increased exposure puts these individuals more at risk than average person. Titanium dioxide is listed as a safe pigment, with no known adverse effects. It is not listed as a carcinogen, mutagen, teratogen, comedogen, toxin or as a trigger for contact dermatitis in any other safety regulatory publications beside NIOSH (Antczak, 2001; Physical & Theoretical Chemical Laboratory, Oxford University respectively). It is reasonable to conclude then, that titanium dioxide is not a cancer-causing substance and is generally safe for use in foods, drugs, paints and cosmetics. This does not end debate, however, as controversy over safety of one unique form of titanium dioxide still exists.
| | 3 "Healthy" Foods NOT to EatWritten by Ryan Cote
There are three foods that are labeled "healthy," but for reasons I'll outline below, you should stay away from.Food #1: Fruit Juices like Orange Juice and Apple Juice Sure they contain vitamin C and may come from real fruit, but fact of matter is, they are loaded with sugar! Yes, it's natural sugar, but it's still sugar- and we all know sugar turns to fat. They now have fruit juices with half sugar- give them a try instead- they actually taste pretty good. Food #2: Energy/Protein/Meal bars like Balance Bars Some claim to have perfect ratio of protein, fat and carbohydrates- and they do. Some just claim to be a good meal replacement bar because they contain fat and protein, and vitamins and minerals- and they do. But if you take a look at label of most bars, you'll see high fructose corn syrup, sugar and in some bars fractionated oils. It's so self-defeating, it blows my mind. Go with bars that have healthy ingredients such as Clif bars, Luna Bars and Odwalla bars.
|
