Organic Consumers Association


Previous Page

Click here to print this page

Make a Donation!


Phosphate Rock Fertilizer: Toxic Metals, Radiation Hazards, Fluoride,
and Organic Growing

George Glasser - Ros Jones
National Pure Water Association
Campaign for Safe Drinking Water
Founded in England, 1960

The NPWA has a long-standing concern about the phosphate fertiliser industry. Fluorosilicic acid (H2SiF6), used to fluoridate drinking water, is derived from the pollution scrubbing operations at those facilities. We have built up a considerable understanding of phosphate rock (PR).

The raw rock (which during phosphate fertiliser production is extensively processed) is contaminated with heavy metals, radionuclides, other toxic metals and fluorides. It is recommended for use as an organic fertiliser in its raw state.

In the process to make the raw rock into green phosphoric acid, some of the fluorides are driven off as silicon tetrafluoride gas and a good amount of the toxic metals/radionuclides are carried away in the gypsum waste stream.

PR is referred to in geological terms as fluorapatite. Depending on the region of the world it comes from, the rock can contain anywhere from 2.0% to 5.0% fluoride. At five percent, one kilogram contains enough fluoride to fluoridate 50,000 litres of drinking water.

One ounce @ 5.0% fluoride (about the amount used to fertilise one organic tomato plant as recommended by some organic growers) contains about 1.4 grams of fluoride, which is enough to kill a small child.

Fluoride is also toxic to many plants (phytotoxic).,, file&file_id=SR00036.pdf

Aside from fluorine pollution, Naturally Occurring Radioactive Materials (NORM) is the major concern of most government environmental agencies regulating pollution and phosphorgypsum waste from the manufacture of phosphoric acid.

Again, depending on geographic location where the PR is mined, it can contain from 50 - 200 ppm of uranium. PR is the major source of 'yellow cake' (uranium oxide) for nuclear weapons and the nuclear power industry.

PR is notorious for its radioactive constituents. The risks it poses are most threatening to people who come into direct contact with it - eg. organic growers. However, organic growing organisations seem to be oblivious to these health hazards - despite the information having been available for many years.

Where there is uranium in natural rock formations, there will also be all its carcinogenic decay rate products; such as radium, radon, radioactive lead, polonium, thorium, etc.

There are also toxic metal contaminants such as beryllium, manganese, arsenic, lead, mercury, cadmium and vanadium.

The tailings from phosphoric acid production (phosphate fertiliser), phosphorgypsum, are so radioactive that they are not allowed to be used for wall-board or road beds in the US and Canada - because it is considered a radiation hazard. However, organic growers are allowed to treat their fields with the raw, unprocessed product once every six years, with none of the contaminants processed out.

Taking a closer look at this 'natural' PR mix, we find for example polonium-210:
One particle of polonium-210 gives off 5,000 times more alpha radiation than the same amount of radium. Damage occurs in the body from complete tissue absorption of the energy of the alpha particle. Polonium-210 can be carcinogenic to people exposed to more than 0.03 microcuries (6.8 trillionths of a gram). Polonium-210 has a half-life of about 138 days.(There are also high levels of Radium and Polonium- 210 in granite dust, which is used by organic farmers is some parts of the world as a soil conditioner).

Half Life: Half of the polonium gives off intense alpha radiation for 138 days until it turns into regular lead and becomes stable. However, half the polonium still remains, emitting alpha radiation for another 138 days; then a quarter of the original amount, and so on and so on.

Polonium is found in tobacco grown with phosphate fertilisers. Studies have suggested that radioactive polonium may be the primary cause of smoking-related cancers.

Polonium is carried throughout the body in the blood. It has been linked to more soft-tissue cancers than bone cancers; typical sites are the liver, spleen and kidney.

Radon is also given off from PR and ground granite. Radon is second only to smoking as the leading cause of lung cancer in the UK.

Radon is an important environmental hazard, due to its release of alpha particle radiation. It has a half life of 3.8 days.

Radon is also soluble in water.

Radon, in and of itself, is not a carcinogen. It is the decay products of radon that are the problem.

If organic growers are using PR or ground granite, they are being exposed to these radioactive elements, especially radon. It is important to note that these do not simply dissipate from the product in a few days, months or years - these products will emit radon for many thousands of years.

NPWA would strongly recommend organic growers to purchase a radon detector/s. PR dust can be brought into the home on clothes and shoes.

Also, greenhouse growers should check for radon build-up.

If you use PR or ground granite for indoor plants, it would be wise to purchase a radon detector and to re-pot your plants.

NPWA believes that the promotion of PR and ground granite soil conditioners by organic growers' organisations endangers the health and well-being of their members and of people who follow their advice.

NPWA also believes that the use of raw phosphate rock and ground granite for fertiliser and/or soil conditioner should be banned for health and safety reasons.

Other reasons for NPWA opposition to the use of PR are as follows:

1. The use of phosphate fertilisers is a major contributor to environmental pollution.

2. The act of mining PR causes ecological devastation in many regions of the world.
3. Concern about up-take of fluorides, toxic metals and radionuclides in produce grown with phosphate fertilisers..
4. The health and wellbeing of growers who have not been informed about the dangers in using PR.

Further Reference Material:

Phosphates -
Phosphate rock used for fertiliser is a major NORM due to uranium and thorium. Australian phosphate rock contains up to 900 Bq/kg and that imported is about twice this, yielding about 1000 Bq/kg in phosphogypsum waste stream and up to 3000 Bq/kg in the superphosphate product. In the USA some 50 million tonnes per year are produced and state figures (UNSCEAR 1977) average up to 10,000 Bq/kg of total radioactivity. Processing this sometimes gives rise to measurable doses of radioactivity to people. Phosphate rocks containing up to 120 ppm U have been used as a source of uranium.

European fertiliser manufacturing gave rise to discharges of phophogypsum containing significant quantities of Ra-226, Pb-210 and Po-210 into the North Sea and North Atlantic. This has been overtaken by offshore oil and gas production in Norwegian and UK waters releasing some 10 TBq/yr of Ra-226, Ra-228 & Pb-210 - contributing 90% of alpha-active discharges in those waters (two orders of magnitude more than the nuclear industry, and with this NORM having higher radiotoxicity).

Also see: