Yes, numerous eco-friendly alternatives exist that can mitigate the environmental impact attributed to synthetic fibers in fast fashion. Here are a few examples:

1. Organic Cotton: Unlike conventional cotton, organic cotton is grown without harmful pesticides or synthetic fertilizers. It is a renewable resource, biodegradable and typically uses less water.

2. Hemp: Rugged yet comfortable, hemp resists pests naturally and grows quickly with less water. It returns up to 70% of its nutrients back to the soil, making it a sustainable option.

3. Linen: Made from the flax plant, linen is another sustainable alternative. It grows easily with little water and is biodegradable. Plus, every part of the plant can be used, reducing waste.

4. Bamboo: This fast-growing plant requires no pesticides or synthetic fertilizers, making it an environmentally friendly choice. However, watch out for the processing method used to turn bamboo into fabric, as some procedures involve harsh chemicals.

5. Tencel/Lyocell: Made from sustainably-sourced wood pulp, Tencel or Lyocell undergo a closed-loop production process where almost all chemicals used are recaptured and reused. It also requires less energy and water in its production compared to traditional fibers.

6. Recycled Fabrics: Increasingly, brands are turning to recycled fabrics (such as recycled cotton, polyester or nylon) for their clothing, which reduces the dependency on virgin materials and minimizes waste. 

7. Pi?atex: This unique fabric made from pineapple leaf fibers serves as an excellent eco-friendly substitute for leather. It eliminates the need for harmful chemicals in processing and creates a durable, versatile material.

8. Algae-based Fabrics: Emerging innovations have resulted in textiles derived from algae. These fabrics are renewable and often come with benefits such as being naturally odor-resistant.

Each of these alternatives have their own benefits and challenges, and it's crucial that the fashion industry invests in sustainable farming and processing practices to ensure that these alternatives are indeed less damaging than their synthetic counterparts.