While several towns have had problems with lead in their water, the main route for lead entering the bloodstream seems to be from the soil. The lead content in the water can be controlled by chemical means that I reviewed recently. Lead in the soil can not be controlled. The average concentration of lead in US water is less than 1 ppb, with 15 ppb as the legal limit. According to the US geological survey, of lead in the soil, 2014., the average concentration of lead in US soil is about 20 ppm. That’s more than 1000 times the legal limit for drinking water, and more than 20,000 times the typical water concentration. Lead is associated with a variety of health problems, including development problems in children, and 20 ppm is certainly a dangerous level. Here are the symtoms of lead poisoning.

Several areas have deadly concentrations of lead and other heavy metals. Central Colorado, Kansas, Washington, and Nevada is particularly indicated. These areas are associated with mining towns with names like Leadville, Telluride, Silverton, Radium, or Galena. If you live in an areas of high lead, you should probably not grow a vegetable garden, nor by produce at the local farmer’s market. Even outside of these towns, it’s a good idea to wash your vegetables to avoid eating the dirt attached. There are hardly any areas of the US where the dust contains less than 1000 times the lead level allowed for water.

Breathing the dust near high-lead towns is a problem too. The soil near Telluride Colorado contains 1010 mg/kg lead, or 0.1%. On a dust-blown day in the area, you could breath several grams of the dust, each containing 1 mg of lead. That’s far more lead than you’d get from 1000 kg of water (1000 liters). Tests of blood lead levels, show they rise significantly in the summer, and drop in the winter. The likely cause is dust: There is more dust in the summer.

Produce is another route for lead entering the bloodstream. Michigan produce is relatively safe, as the soil contains only about 15 ppm, and levels in produce are generally far smaller than in the soil. Ohio soils contains about three times as much lead, and I’d expect the produce to similarly contain 3 times more lead. That should still be safe if you wash your food before eating. When buying from high-lead states, like Colorado and Washington, you might want to avoid produce that concentrates heavy metals. According Michigan State University’s outreach program, those are leafy and root vegetables including mustard, carrots, radishes, potatoes, lettuce, spices, and collard. Fruits do not concentrate metals, and you should be able to buy them anywhere. (I’d still avoid Leadville, Telluride, Radium, etc.). Spices tend to be particularly bad routes for heavy metal poisoning. Spices imported from India and Soviet Georgia have been observed to have as much as 1-2% lead and heavy metal content; saffron, curry and fenugreek among the worst. A recent outbreak of lead poisoning in Oakland county, MI in 2018 was associated with the brand of curry powder shown at left. It was imported from India.

Marijuana tends to be grown in metal polluted soil because it tolerates soil that is too polluted fro most other produce. The marijuana plant concentrates the lead into the leaves and buds, and smoking sends it to the lungs. While tobacco smoking is bad, tobacco leaves are washed and the tobacco products are regulated and tested for lead and other heavy metals. If you choose to smoke cigarettes, I’d suggest you chose brands that are low in lead. Here is an article comparing the lead levels of various brands. . Better yet, I’s suggest that you vape. There are several advantages of vaping relative to smoking the leaf directly. One of them is that the lead is removed in the process of making concentrate.

Some states test the lead content of marijuana; Michigans and Colorado do not, and even in products that are tested, there have been scandals that the labs under-report metal levels to help keep tainted products on the shelves. There is also a sense that the high cost encourages importers to add lead dust deliberately to increase the apparent density. I would encourage the customer to buy vape or tested products, only.

Here is a little song, “pollution” from Tom Lehrer, to lighten the mood.

Robert Buxbaum, November 24, 2019. I ran for water commissioner in 2016 and lost. I may run again in 2020. Who knows, this time I may win.