The tea sector employs 15 million people in more than 80 countries. China is the largest producer, accounting for about 38 percent of tea production. Monoculture farming is common, leading to pests and nutrient-poor soils, a high level of pesticide and fertilizer use, and polluted groundwater. Most of the tea consumed worldwide is produced by small farmers, but they are unable to live on their earnings, given fluctuating global market prices and wages that are below subsistence level. Ten-hour days, child labour and sexual assaults against women are not uncommon – as is poor hygiene, which affects the supply of drinking water, for example. Since tea products, and especially tea blends, contain multiple components, there is often a lack of transparency concerning the origins of the raw materials. This makes it difficult to address social and environmental challenges.