Measuring Heavy Metals
Arsenic is a nasty heavy metal that can be easily measured by practitioners.
I have recently been taking a deeper look into the effects of heavy metals and their sources and am coming up with some interesting articles. For example a report that discusses the levels of arsenic in apple juice, apple concentrates and pear juices.
Harmful Effects of Arsenic
In this day and age we usually think of arsenic as ‘that poison’ that killed off somebody in those old fashioned movies or mysteries. In the 1800’s arsenic proved fatal for many people as it covered the walls of upmarket houses as wallpaper and was even used as medicine.
But in reality arsenic is still with us and doing harm that most of us are unaware of. In fact arsenic is linked to numerous health and skin issues. Thankfully our exposure is fairly limited these days so chronic symptoms are more common than acute symptoms.
We know that arsenic is linked to numerous skin conditions of the skin, hair and nails including skin eruptions, skin pigmentation issues, alopecia (hair loss). nail striation, dermatitis, warts and more. Numerous other health related symptoms have been linked to chronic exposure. Cancer of the skin, lung and liver are some of the major concerns associated with arsenic in the body.
An assessment of the Joint Food and Agriculture Organization/World Health Organization (FAO/WHO) Expert Committee on Food Additives (JECFA) concluded that food can be a major contributor to inorganic arsenic exposure. The European Food Safety Authority (EFSA) concluded that dietary exposure to inorganic arsenic should be reduced.
Apple juice is one source of exposure to inorganic arsenic from food. This is of particular concern in children as their consumption tends to be higher than that of adults relative to their body weight.
Arsenic levels can be measured and safe treatment options to remove the heavy metal from the body, are possible.
FDA Acceptable Levels of Inorganic Arsenic
The FDA has established the acceptable level of inorganic arsenic in single-strength apple juice of 10ug/kg or 10 ppb. This level will be protective against adverse effects associated with short term exposure and non-cancer endpoints – the level of concern was 23 ppb.
Arsenic has been found in a variety of food sources and in 2011 the FDA initiated a quantitative risk assessment based on childhood, chronic and lifetime exposure and cancer endpoints. Their research was particularly interested in inorganic arsenic that has been associated with cancer, skin lesions, developmental effects, cardiovascular disease, neurotoxicity and diabetes in humans.
Dietary Sources of Arsenic
Since 1991 apple juice has been under regular surveillance by the FDA in regards to its arsenic content. This has resulted in the lowering of arsenic levels and in 2011, 95 percent of the 94 apple juice samples collected were below 10 ppb. Draft guidance was issues by the FDA at this time in an attempt to further reduce inorganic arsenic in apple juice.
Allowable levels of arsenic in bottled water has similarly been set at 10 ppb.
In chickens inorganic arsenic was identified in edible tissue, especially the liver. The source was an approved animal drug known as roxarsone or 3-Nitro. In the United States, sales of roxarsone were voluntarily suspended by Alpharma.
Investigations are also being done into rice and rice products, which compared to other plant foods, has relatively high levels of total and inorganic arsenic.
Possible sources of arsenic that gets into our food supply includes;
- arsenic based pesticides
- naturally high levels of arsenic in soil and water
- atmospheric deposition from industrial activities.
The committee (JECFA) recommended that the levels of arsenic in fish should be investigated further. Although arsenic levels are high in fish and shellfish, it should be noted that the majority of arsenic is the less harmful organic arsenic.
Geographic Areas and High Arsenic
The committee noted that there is a need for more information about arsenic accumulation in relation to diet and drinking water and epidemiological studies of populations with elevated exposure.
In Bangladesh the mean dietary exposure to inorganic arsenic was estimated to be up to 3 times that in
other Asian countries. Mean dietary exposure to inorganic arsenic for adults in a community in Chile was 7 times higher at the upper end of the reported range than that reported for adults elsewhere.
In areas such as Bangladesh, contaminated water can contribute up to 50% of total dietary exposure. In Australia a large part of our rice supply comes from Bangladesh and neighbouring countries and we should therefore be wary of where our rice is grown.
There are concerns about arsenic levels in Japan where a large percentage of the population consume high amounts of edible algae and seaweed. Inorganic arsenic can be very high in these foods, which are eaten on a daily basis.
How to reduce arsenic exposure in food
To reduce arsenic exposure it is recommended that vegetables be peeled. Rice should be polished by washing or soaking. Seaweed should also be washed or soaked in water to reduce arsenic levels. Boiling water has been found to decrease arsenic levels in seaweed, rice, pasta and seafood products.
WHO Technical Report Series 959. Evaluation of Certain Contaminants in Food. Seventy-second report of the Joint FAO/WHO Expert Committee on Food Additives.
FDA. Supporting Document for Action Level for Arsenic in Apple Juice. July 2013.Arsenic, Apple Juice and Skin Cancer – Is there a link??