Lead in soil is always something to monitor

SOME years ago, I wrote an article for Organic NZ magazine about lead in the home garden as it is an issue gardeners need to be aware of.

If lead is found in high levels in the soil, it will be taken up by plants. The main sources of lead contamination in home gardens are old paint that has flaked off buildings and fences, and leaded petrol residues from areas close to roads.

As a general rule, lead is found in higher quantities in the leaves of a plant, rather than in the fruits or seeds. Brassicas (broccoli, cabbage, kale and so on) take up lead more than other plants. In fact, mustard greens (or Indian mustard) have been used for remediation, to remove lead from soils.

Leafy vegetables such as lettuces and spinach are likely to have a higher lead load if there is lead present in the soil. Lead may also be found on the surface of root crops such as carrots and potatoes.

Thoroughly washing all soil off, removing outer leaves of leafy vegetables, and peeling or vigorously scrubbing root crops will go some way towards reducing any lead that may be there.

Plants that we eat the fruit and seeds of are not usually a concern. These include tomatoes, capsicums and eggplants; pumpkins, zucchinis, cucumbers and other cucurbits; peas, beans and grains like corn or wheat. An exception to this rule is the sunflower (seed).

Fruit from trees, bushes or brambles is unlikely to contain enough lead to worry about.

Philippa Jamieson Opoho

Milk protein

THE information from Quantec that independent US laboratory research has found the milkderived ingredient IDP (immune defence proteins) to be effective against influenza virus species (ODT, 30.12.20) and against stress (ODT, 15.1.21) is very good news.

As Quantec is also eyeing IDP as a barrier against Covid19, it would surely be wise for those of us who can tolerate milk products to choose the less processed brands which it seems can create a barrier to stop the virus entering the body cells.

C. Fitzgibbons Mornington

BIBLE READING: The Lord is my shepherd, I shall not want. — Psalms 23:1.