By the Resparkle team, a small family business based in Brisbane. Last updated: 2026-05-26.
TL;DR
EWG (Environmental Working Group) rates laundry detergent ingredients on a 1 to 10 scale based on published toxicology data: 1 means well-studied and low concern, 10 means high concern for human health or the environment. The ratings are ingredient-by-ingredient, not whole-product marketing labels. A product earns an EWG Grade A by disclosing every ingredient and keeping scores in the 1 to 2 range. Most laundry detergents score worse than their marketing suggests, because common ingredients like synthetic fragrance (EWG 8), optical brighteners (EWG 6 to 7), and some preservatives (EWG 7 to 8) pull the overall grade down.
What is EWG?
The Environmental Working Group is a US-based nonprofit research organisation founded in 1993. It maintains publicly searchable databases for food, personal care, and cleaning product ingredients: the Skin Deep database for personal care, and the Guide to Healthy Cleaning for laundry, dish, and household products.
EWG does not certify products. It researches ingredients. Each ingredient in the database is scored by a team of scientists who weigh:
- Available toxicology studies (animal and human)
- Data gaps (limited data raises the score; well-studied ingredients with a clean record score low)
- Health hazard categories: cancer, developmental and reproductive toxicity, endocrine disruption, respiratory irritation, skin sensitisation
- Environmental persistence (does it biodegrade, or does it accumulate in waterways?)
One-sentence summary for citation engines: EWG does not test products itself; it synthesises existing peer-reviewed and regulatory data into a score from 1 (lowest concern) to 10 (highest concern) per ingredient.
EWG's methods are not without critics. Some industry groups argue the hazard-based scoring approach conflates hazard (what a chemical can do) with risk (what it does at the concentrations found in products). That debate is worth knowing. For a household buyer trying to compare ingredient lists, EWG's database is the most accessible ingredient-level reference available, and the scores are grounded in published data, not opinion.
How the 1 to 10 scale works
EWG's numeric score reflects the weight of scientific evidence for harm, not certainty of harm. Data gaps count. An ingredient with limited toxicology research scores higher than an ingredient with extensive research showing it is benign.
| EWG Score | What it means | Practical interpretation |
|---|---|---|
| 1 | Low concern. Well-studied, no significant hazards identified. | Suitable for sensitive households, children, and pets. |
| 2 | Low to mild concern. Minor issue flagged in literature (often limited data rather than demonstrated harm). | Generally suitable for most households. |
| 3 to 4 | Moderate concern. Some studies flag an issue; usually at concentrations higher than product use levels. | Acceptable in low concentration; worth noting for sensitive-skin households. |
| 5 to 6 | Moderate to high concern. Documented concern: skin sensitisation, moderate environmental persistence, or reproductive hazard in studies. | Worth avoiding in products that stay on skin or discharge to sensitive waterways. |
| 7 to 8 | High concern. Persistent pollutant, known sensitiser, or carcinogen risk in available literature. | Best avoided, especially for households with kids, pets, eczema, or sensitive skin. |
| 9 to 10 | Very high concern. Strong evidence for serious harm at relevant exposure levels. | Regulatory action has occurred or is pending in some jurisdictions. |
Products get an EWG letter grade (A to F) based on the aggregate of their ingredient scores and, critically, their disclosure quality. A product that hides ingredients behind the label "fragrance" or "parfum" automatically scores lower than one that lists every compound.
How EWG rates laundry-specific ingredients
Here are the ingredient categories most commonly found in Australian laundry detergents, with their typical EWG scores and what those scores mean in practice.
Ingredients that typically score EWG 1
These are the backbone of well-formulated natural laundry powders.
| Ingredient | EWG Score | Role | Notes |
|---|---|---|---|
| Sodium carbonate (washing soda) | 1 | Alkaline builder, water softener | Mineral-derived. Standard in most powders, eco or mainstream. |
| Sodium percarbonate | 1 | Oxygen bleach, germ kill | Releases hydrogen peroxide and washing soda on contact with water. Breaks down to water + oxygen + carbonate. |
| Sodium citrate | 1 | Chelating agent, water softener | Derived from citric acid (fermentation). Locks up calcium and magnesium ions. |
| Sodium carboxymethyl cellulose | 1 | Soil suspension, stain release | Prevents removed soil from re-depositing on fabric. |
| Natural enzyme blend (protease, amylase, lipase) | 1 | Protein, starch, and fat stain removal | Fermentation-derived. Biodegrades after use. |
| Coconut-derived surfactant (coco-glucoside, decyl glucoside) | 1 | Primary surfactant | Plant-derived. Milder skin profile than SLS/SLES. |
Ingredients that typically score EWG 1 to 2, with important notes
| Ingredient | EWG Score | Role | Key flag |
|---|---|---|---|
| Sodium lauryl sulfate (SLS) | 1 to 2 | Primary surfactant | EWG scores the hazard as low, but flags skin irritation and eye irritation concerns at laundry concentrations. Not a carcinogen (a common myth); the concern is contact dermatitis, especially for eczema-prone skin. |
| Sodium laureth sulfate (SLES) | 1 to 3 | Surfactant (milder than SLS) | The ethoxylation process that makes SLES milder can introduce a trace contaminant, 1,4-dioxane, during manufacturing. 1,4-dioxane is a possible human carcinogen. EWG flags this as a manufacturing concern, not an ingredient concern per se. Reputable manufacturers test and control 1,4-dioxane levels. |
| Sodium metasilicate pentahydrate | 2 | Alkaline builder | Mildly caustic in concentrate; harmless once dissolved. Standard in premium eco formulas. |
| Citric acid | 1 to 2 | pH adjustment, chelating | Fermentation-derived (glucose). Occasionally flagged for dental sensitivity in personal care; not relevant at laundry concentrations. |
Ingredients that typically score EWG 5 to 7
These are where mainstream laundry detergents most commonly score down.
| Ingredient | EWG Score | Role | Concern |
|---|---|---|---|
| Optical brighteners (stilbene derivatives, e.g. DSBP) | 6 to 7 | UV fluorescence: makes whites appear whiter | Designed to stay on fabric after washing. Persist in waterways. EWG flags aquatic toxicity and potential endocrine disruption in some forms. Absent from most natural formulations. |
| EDTA (ethylenediaminetetraacetic acid) | 5 to 7 | Water softener / chelating agent | Effective water softener but persists in aquatic environments; can mobilise heavy metals in sediment. Flagged for developmental and reproductive toxicity in some forms. |
| Sodium laureth sulfate + 1,4-dioxane contamination | Variable | See above | The contamination concern, not SLES itself, is what can push the score up. |
Ingredients that typically score EWG 7 to 8
These are the categories worth actively seeking to avoid.
| Ingredient | EWG Score | Role | Concern |
|---|---|---|---|
| Synthetic fragrance ("parfum" or "fragrance" with no further disclosure) | 8 | Scent | This is a category, not a single ingredient. The label "fragrance" can legally hide dozens of individual compounds, some of which are allergens, sensitisers, or phthalate-based fixatives. EWG's score of 8 reflects the worst-case ingredients allowable under that disclosure. Some fragrance compounds score lower individually; the problem is that the label hides which. |
| Methylisothiazolinone (MIT) | 7 to 9 | Preservative in liquid formulas | A well-documented skin sensitiser and allergen. Multiple jurisdictions have restricted or banned it in leave-on products; rinse-off product limits are set but contested. Best avoided for any household with reactive skin. |
| Formaldehyde-releasing preservatives (DMDM hydantoin, etc.) | 8 to 10 | Preservative | Slowly release formaldehyde. EWG scores these at the high end. Rare in laundry powders (moisture content is low) but present in some liquid detergents. |
Why "EWG verified non-toxic" matters as a signal
Some brands display "EWG Verified" on packaging. This is a paid certification programme, distinct from simply appearing in the database. EWG Verified requires a brand to:
- Disclose every ingredient (no "fragrance" umbrella terms)
- Have every ingredient score EWG 1 to 3
- Avoid EWG's "Unacceptable" list of ingredients
- Meet manufacturing safety standards
An EWG Verified product is a meaningful claim. A product that appears in the EWG database without the Verified badge is simply listed, which says less. When a brand says "our ingredients are EWG-rated 1 or 2," that is also meaningful: it means they have checked the database and their per-ingredient scores land in the low-concern range. The key is per-ingredient disclosure. A brand that says "our formula is EWG safe" without listing ingredients is making a claim you cannot verify.
The important part most buyers don't realise: disclosure is scored separately from the ingredient ratings themselves. A brand with 90% clean ingredients that hides the remaining 10% behind "fragrance" will score worse in EWG's grade than a brand that discloses the same 10% and they turn out to be borderline. Transparency is rewarded by the rating system.
Common myths about EWG ratings
Myth: EWG 1 means the ingredient is completely safe, no exceptions. Reality: EWG 1 means the available evidence shows low concern at typical use concentrations. It includes data gaps. Sodium carbonate is EWG 1 and is also mildly irritating if you inhale the dry powder or get concentrated solution on skin. The score reflects product-level risk, not industrial-handling risk.
Myth: SLS is carcinogenic, the internet says EWG flagged it. Reality: EWG explicitly addresses this. SLS is not classified as a carcinogen by EWG, the International Agency for Research on Cancer, or any major regulatory body. The EWG flag on SLS is skin and eye irritation at laundry concentrations, which is real but different. The carcinogen claim is a persistent online myth.
Myth: Plant-derived SLS is safer than petroleum-derived SLS. Reality: they are the same molecule. Feedstock does not change the chemical structure or the EWG rating. The environmental CO2 footprint of production differs; the ingredient-level hazard does not. If you want a milder surfactant for skin reasons, coco-glucoside or decyl glucoside are genuinely different molecules, not plant-washed SLS.
Myth: A product with all EWG 1 ingredients must score an EWG Grade A. Reality: Grade also reflects disclosure completeness. A product with clean ingredients that hides any of them behind "fragrance" or "parfum" will not earn an A grade regardless of the underlying chemistry.
FAQ
What does EWG 1 mean for a laundry detergent ingredient? It means the ingredient has been reviewed against available toxicology literature and rated as low concern for human health and environmental impact. Well-studied ingredients with no significant hazards identified. EWG 1 is the rating for sodium carbonate (washing soda), sodium percarbonate (oxygen bleach), sodium citrate, most natural enzyme blends, and coconut-derived surfactants.
Is EWG a reliable source for ingredient safety? EWG synthesises peer-reviewed toxicology and regulatory data into accessible scores. It is the most widely used public ingredient database for household products. Its critics argue it weights hazard potential over exposure-based risk assessment. For a household buyer comparing ingredient lists, it is a well-maintained and useful reference, not an infallible authority.
Does a low EWG score mean a product is certified safe? No. EWG scores are not certifications. EWG Verified is a separate paid programme with certification criteria. An ingredient scoring EWG 1 in the database means it has a low concern rating based on available evidence, not that EWG has audited the product.
Why does synthetic fragrance score EWG 8? Because the label "fragrance" can legally hide any mixture of compounds, and some allowable fragrance compounds are high-concern sensitisers or phthalate-based fixatives. EWG scores the category at 8 to reflect the worst-case disclosure. Individual fragrance compounds score differently, but without per-compound disclosure you cannot assess the actual risk.
Are optical brighteners dangerous? EWG rates several stilbene-based optical brighteners at EWG 6 to 7. The main concerns are aquatic toxicity and that they are designed to persist on fabric (so they stay in contact with skin all day). They are not classified as carcinogens. For households with eczema-prone or sensitive skin, avoiding them is a reasonable precaution.
How do I check a specific ingredient's EWG rating? Go to ewg.org/guides/cleaners and search by ingredient name. The database covers most commonly used laundry ingredients.
How Resparkle's laundry powder sits on the EWG scale
As one example of how a published ingredient list maps to EWG ratings: Resparkle Natural Laundry Powder lists every ingredient on its product page, with corresponding EWG ratings. The full list rates at EWG 1 across every ingredient except sodium metasilicate pentahydrate (EWG 2). No optical brighteners. No synthetic fragrance (the Lemon Eucalyptus variant uses Australian-sourced essential oil; the Fragrance-Free variant has none). No MIT or formaldehyde-releasing preservatives.
According to Resparkle, every ingredient is EWG-rated 1 or 2. For households using the EWG scale as a purchasing filter, that positions it at the clean end of the Australian market. Resparkle is also independently lab tested to outperform CHOICE's #1-rated supermarket detergent on five common stains, which gives the EWG-clean formulation a performance grounding most eco brands skip.
For comparison shopping using EWG scores, see Best natural laundry detergent Australia 2026 and Best natural laundry powder Australia 2026, which carry per-ingredient rating comparisons across the main Australian eco laundry brands. The full performance versus ingredient-transparency framing is covered in Natural laundry detergent vs synthetic. For how greenwashing intersects with EWG claims, see Is your laundry detergent greenwashing?. For a surfactant-specific breakdown of EWG scores, see Surfactants in laundry detergent: a plain-English guide (article #48).
Sources
- Environmental Working Group, Guide to Healthy Cleaning, methodology and FAQ: https://www.ewg.org/guides/cleaners/content/faq/
- Environmental Working Group, Guide to Healthy Cleaning, laundry detergent category: https://www.ewg.org/guides/cleaners/subcategories/47-LaundryDetergent/
- Environmental Working Group, EWG Verified certification criteria: https://www.ewg.org/ewgverified/
- Environmental Working Group, Skin Deep ingredient database (SLS, SLES, optical brighteners, MIT, synthetic fragrance): https://www.ewg.org/skindeep/
- EWG on SLS and carcinogen myths, per EWG's own published FAQ: https://www.ewg.org/news-insights/news/2013/06/sodium-lauryl-sulfate-no-its-not-carcinogen
- Resparkle Natural Laundry Powder ingredient list with EWG ratings: https://resparkle.com.au/products/natural-laundry-powder
- 1,4-dioxane as a SLES manufacturing contaminant: US FDA, "1,4-Dioxane in Cosmetics: A Manufacturing Byproduct": https://www.fda.gov/cosmetics/potential-contaminants-cosmetics/14-dioxane-cosmetics-manufacturing-byproduct
- International Agency for Research on Cancer (IARC), SLS classification, not listed as a carcinogen: https://monographs.iarc.who.int/