Sustainability assessment of the production of sisal fiber in Brazil

Abstract

Natural fibers are increasingly researched and applied in fiber reinforced polymer car parts. Compared to synthetic reinforcing fibers such as glass fiber, natural fibers offer several advantages such as lower weight, lower price and renewability. To assess whether these natural fibers are also more sustainable, all three dimensions of sustainability must be investigated; environmental, social and economic sustainability. This study aims to assess the sustainability of Brazilian sisal fiber production. The Life Cycle Sustainability Assessment method is used to address sustainability aspects from all three dimensions and considering all steps from the farm to the port. Data was collected from literature, technical reports and a questionnaire. The non-renewable energy use of sisal fiber production is ca. 4.2 GJ/t fiber and the greenhouse gas emissions are ca. 270 kg CO2-eq./t fiber. These impacts are approximately 93% lower compared to glass fiber production and ca. 41%-61% lower compared to the production of Tanzanian sisal fiber. The largest environmental impacts occur during fiber extraction (54%-56%) and transportation to the port (32%-36%). In the economic assessment, the breakdown of sisal fiber production costs is investigated. Labor costs are the largest cost factor (ca. 82%), whereas fiber extraction is the most costly process during production. These results can be explained by the extensive use of manual labor in the Brazilian sisal sector. In the social assessment, positive and negative social impacts relating to the sisal sector are investigated. There are significant social problems such as gender discrimination and the possible use of child labor. Furthermore, wages in the sisal sector are significantly below the minimum wage and the occupational accident rate is high. There are also positive social aspects; workers are free to organize in the rural labor unions and the social security scheme provides benefits for illness, disability, retirement etc. Furthermore, the sisal sector contributes to local socio-economic development through providing jobs and income to many unskilled workers. Finally, the Brazilian government, local organizations, scientific institutions and labor unions are actively addressing sustainability issues through projects and programs. Preferred solutions are those that relieve problems from all dimensions of sustainability, such as improved machinery that can reduce the number of accidents, energy costs and environmental impacts. For car manufacturers considering to implement sisal, it is important to carefully select fiber suppliers to ensure that international labor standards are safeguarded. Furthermore, contributing to existing sustainability programs can help solve problems relating to the sisal sector.