Last week, world leaders and members of the international climate community met at the United Nations to agree on a set of Sustainable Development Goals. As one of the most globalized industries, the fashion and apparel sector has an important role to play in building more sustainable and inclusive growth models. Here are four reasons why the fashion sector needs to speak up on climate in 2015.

1. The textile industry is the world’s second largest polluter of clean water

While tremendous progress has been made with the Millennium Development Goals, the least on-track goal is that of halving the number of people without access to safe drinking water and basic sanitation. Around the world, 2.5 billion people still lack basic sanitation facilities, and things look set to get even more challenging: water use is predicted to increase by 50% between 2007 and 2025 in developing countries and 18% in developed ones

The textile industry is one of the largest polluters of clean water, and 20% of industrial water pollution is due to textile dyeing and treatment. In fact, the situation has got so bad that in some apparel manufacturing powerhouses such as Bangladesh and India, you can even see what colours are “in” by looking at the dyes in the canals and rivers.

Organizations like Cradle to Cradle are helping companies manage this precious resource, and address the impact at the local level. But companies, international organizations and governments still need to establish how they can work together to improve their water management.

2. Your closet might actually be toxic

While the rivers in South Asia might be running red when crimson is in season, it’s not just the colour we need to worry about. There are many chemicals and toxins that go into manufacturing clothes; some of these affect our natural environment and can even come out when we wash our clothes.

For example, the waterproof finish of a rain jacket is made by highly fluorinated compounds that have been associated with adverse neurological effects, and the process of distressing jeans exposes workers to cotton and silica dust. It’s not just workers being exposed to the dangers: consumers are, too. While the American Apparel and Footwear Association maintains a list of 250 restricted substances, many of them are highly unregulated in the places they are made. Greater coordination across industry and government is needed to ensure that our closets aren’t harming people and the environment.

3. Diamonds aren’t a girl’s best friend

Since the discovery of the first diamond mine, the industry has had to contend with smuggling, violence and environmental issues. These issues came to global attention through the blood diamonds of the civil wars in Angola, the Democratic Republic of Congo, Côte D’Ivoire and Sierra Leone. Consumers responded by buying diamonds from conflict-free countries like Canada and, in some cases, boycotting diamonds altogether.

The Kimberly Process, a certification scheme designed by governments, industry and civil society, aimed to stem the flow of these conflict diamonds. Although the scheme has helped reduce the number of conflict diamonds on the market, there are still too many loopholes. Others have pointed out that the scheme is too narrow and doesn’t take into account the unfair labour practices and human rights abuses in the industry, such as in the Marange diamond fields in Zimbabwe.

Many companies have implemented initiatives that trace raw materials, and their efforts should be lauded, scaled up and replicated. Best practices and standards have also been developed, such as the UN Guiding Principles for Business and Human Rights and the OECD’s Due Diligence Guidance for Responsible Supply Chains of Minerals from Conflict-Affected and High-Risk Areas.

However, further multistakeholder collaboration is needed to unite the fragmented jewellery industry value chain. In an age where we can scan a product’s barcode to find out how ethical and green it is, or understand a company’s commitment to sustainability with the Positive Luxury’s Trust Mark, why can’t we know exactly where a diamond – one of the most expensive accessories many of us will ever buy – comes from?

4. Reinvention is part of the fashion industry’s DNA

Instant online coverage of fashion shows and street style has forced retailers to respond quickly to changing fashion trends. Many companies are already delivering new products monthly and others are delivering new merchandise on a weekly basis. The fashion industry is characterized by speed and change. Wouldn’t it be great if it could use its trend-setting power to take a leadership role on sustainability and create lasting change for the environment? Will the next generation look back on 2015 and see a turning point when the fashion sector took bold action on climate or will it be a missed opportunity? I’m hoping for the former.