Slime, a popular toy and craft material, offers a unique tactile experience. Its widespread appeal has led to questions about its environmental impact, prompting a closer look at its components and where it ends up.
Common Slime Ingredients
The primary component in most homemade and commercially produced slimes is polyvinyl alcohol (PVA), found in white school glues. PVA acts as the long, flexible polymer chains that give slime its fundamental structure. To transform this liquid into an elastic substance, a crosslinking agent is added. Borax, or sodium tetraborate, commonly serves this purpose, reacting with the PVA molecules to form a network that creates slime’s stretchy properties. In some recipes, contact lens solutions containing boric acid and sodium borate fulfill the same crosslinking role.
Beyond these core ingredients, slime often incorporates various additives such as synthetic dyes for color, fragrances for scent, and decorative elements like glitter or small plastic beads.
How Slime Affects the Environment
Slime’s environmental impact largely stems from its synthetic ingredients and disposal. Polyvinyl alcohol (PVA), though water-soluble, does not fully biodegrade under typical wastewater treatment. Studies indicate that 75% to 77% of PVA can persist as microplastics in waterways and soil after dissolution and wastewater treatment. Complete biodegradation requires specific microorganisms and environmental conditions often absent in natural settings or treatment facilities. Once in the environment, undegraded PVA can adsorb and transport contaminants such as heavy metals and various chemicals.
Many slime additives also pose environmental concerns. Glitter, commonly made from plastics like polyethylene terephthalate (PET) and polyvinyl chloride (PVC) along with metallic coatings, functions as a microplastic. Its small size and durable composition mean glitter does not easily degrade, contributing to plastic pollution in oceans, rivers, and soil. Aquatic organisms can ingest these microplastic particles, leading to their entry into the food chain and interfering with biological processes.
Synthetic dyes can contain heavy metals and, if released into waterways, can disrupt aquatic ecosystems by reducing light penetration or exerting toxic effects on organisms. Synthetic fragrances, including musks, can interfere with aquatic life’s detoxification mechanisms and persist in water systems. Improper disposal, particularly washing slime down drains, channels these non-biodegradable components into water systems, contributing to plumbing blockages.
Eco-Friendly Slime Practices
Responsible disposal minimizes slime’s environmental impact. Slime should never be washed down drains, as this allows synthetic ingredients into waterways and can cause plumbing issues. Instead, dispose of used slime in household trash, ideally after drying or in a sealed bag. Slime is generally not recyclable due to its chemical composition and sticky texture.
Exploring alternative, eco-friendly materials can reduce slime’s footprint. Recipes using natural ingredients such as psyllium powder, cornstarch, and water offer a biodegradable base. Other natural alternatives include flaxseed or xanthan gum for texture, combined with cornstarch and water.
For color, natural pigments can be used. For added texture, items like tapioca pearls, rice, or dried beans serve as sustainable alternatives to plastic glitter or microbeads. While some “biodegradable” glitters exist, often made from plant cellulose, research their environmental fate, as some may still contain problematic coatings.