We tested it in the soil, not just on paper. 

Four independent laboratory reports confirming that soil exposed to Carbon Nurture mulch film residue supports plant growth, protects earthworms, and keeps the soil's nitrogen cycle running, exactly like untreated soil does.

Why we tested, and why most films never do 

Not every "biodegradable" mulch film is safe for the ground it's plowed into. Some break down into microplastics that never fully disappear while others leave additive residues behind long after the film is gone. 

Few manufacturers ever put their soil to the test, but we did. 

We sent real soil from our own test fields, soil that had absorbed our film's residuals after biodegradation, to an independent lab for four rounds of ecotoxicity testing, compared against the same untreated soil. Download whichever reports matter most to your work.

The Four Soil Safety Test Reports

Plant Growth: Barley

Barley grown in soil with our film's residuals didn't just match the control group; it grew better, with 106% germination and 24-25% more biomass. 

Tested against: OECD 208, per EN 17033 (Annex B)

Result: Pass, no phytotoxic effects Download: Barley Seedling Emergence & Growth Report

Plant Growth: Cress

Cress represents broadleaf crops, as barley represents grasses. Germination and yield both came in at or above the required 90% of the untreated control. 

Tested against: OECD 208, per EN 17033 (Annex B) 

Result: Pass, no negative effect on emergence or growth Download: Cress Seedling Emergence & Growth Report

Earthworm Survival

Earthworms are a sensitive early indicator of soil toxicity. 100% survived in soil with our film's residuals, matching the control, with body weight staying within 4% of it. 

Tested against: ISO 11268-1 & ASTM E1676, per EN 17033 (Annex C)

Result: Pass, 100% survival Download: Earthworm Acute Toxicity Report

Nitrification Activity

Soil bacteria convert nitrogen into a form plants can use. Nitrite formation in our test soil measured 85% of the control, above the 80% threshold. The nitrogen cycle continues undisturbed. 

Tested against: ISO 15685, per EN 17033 (Annex E)

Result: Pass, no inhibition of nitrifying organisms Download: Nitrification Inhibition Report

Independently Tested for Soil Safety 

All four studies were conducted by Normec OWS nv in Ghent, Belgium, under OECD Good Laboratory Practice principles, with each report signed off by an independent Study Director and QA reviewer. It's laboratory data, not marketing math.

Standards referenced: 

• EN 17033:2018

• OECD 208

• ISO 11268-1

• ISO 15685

• ASTM E1676

Questions about the results? Contact us at tamera@carbonnurture.com