Environmental performance of a household laundry cycle

Laundry is a frequent household activity, performed either manually or by washing machine. This process consumes chemical products (such as laundry detergent and fabric softener), electricity, and water. It is therefore important to understand the environmental impacts and costs associated with laundry. The goal of this paper was to assess its eco-efficiency based on the NBR ISO 14045:2014 standard.

Primary data were collected from laundry detergent and fabric softener producers in Teresina, Piauí, Brazil. Secondary data were collected from patents, a chemical industry association, the government labeling program, and municipal water and electricity suppliers. The product system boundaries were cradle-to-consumer, and the impact categories were global warming, freshwater eutrophication, and land use. The product system value indicator was the washing costs from the consumer's perspective. The environmental and product system value indicators were related using the eco-efficiency formula which resulted in the process eco-efficiency profile. An uncertainty analysis was carried out to measure errors intrinsic to the data and the methods. A sensitivity analysis was carried out to identify the influence of choices made during the study and to propose viable technical improvements.

The results showed that the most impactful processes in the three categories were electricity, wastewater treatment, and the chemical products (laundry detergent and fabric softener). In terms of product system value, the costs of water and sewage treatment had the highest contribution to the overall costs. It was not possible to identify the laundry eco-efficiency profile degree and to calculate the X factor, due to the lack of studies in this area. Greater uncertainties were found in the global warming category, due to its global scope, while freshwater eutrophication category has country-specific characterization factors. A new scenario was proposed to identify possible economically and environmentally feasible changes. However, it did not generate significant changes that would improve the eco-efficiency profile of the evaluated process.

This work highlights the eco-efficiency importance as an environmental management tool to support business decision-making and to identify the environmental impacts of domestic activities. By the results, washers and laundry products manufacturers know which areas they should invest in research and development to reduce their products' impacts. For future studies, it is recommended to evaluate the use of a detergent that does not require fabric softener, such as those sold by the brands Biozgreen, TerpenOil, and Yvy in the Brazilian market, and a high-efficiency washer.