A 'soil your undies' campaign aims to improve plant growth in one district of Ontario. Soil with healthy microbial activity should eat away at the underwear buried six inches deep within eight weeks, leaving only the elastic waistband behind a conservation authority said. So, which is environmentally friendlier, Victoria's Secret or Stanfields? Alas, not British "biodegradable" plastic shopping bags. Researchers from the University of Plymouth found that bags labelled biodegradable and compostable were still able to carry a full load of shopping after being left to degrade in the elements for three years. Conclusion: carry groceries home in your undies.