Wastewater reuse for crop irrigation: Crop yield, soil and human health implications based on giardiasis epidemiology

Highlights: • Water demand is growing twice as fast as the human population. • Agriculture is the major water consumer on the planet. • Wastewater is an alternative to supply the water demand of agricultural sector. • Safe wastewater reuse must consider impacts on environmental and human health. Agriculture is the major water consumer on the planet, it is estimated that 70% of its global use is for this activity. Thus, the reuse of wastewater appears as a viable alternative to supply the water demand of the agricultural sector. Despites to be a common practice since the ancient times, mainly in arid and semi-arid regions, the use of wastewater is still incipient in some regions due to the illusion of water resources abundance or to the lack of infrastructure and investments. In this review we will discuss the reuse of wastewater in agricultural irrigation around the world, its associated risk for crop yield, soil, and public health, and the most common disinfectant processes used to treat WW for crop irrigation. We focused the public health discussion on the waterborne protozoan Giardia lamblia, given to its epidemiological importance, mainly in developing countries.