GLOSSARY

SEQUESTERING AGENTS

These chemicals are able to combine with Calcium and Magnesium in water (or in food traces on crockery), so they make lower their free concentration in water. This action is very useful to have a good washing quality: so Calcium and magnesium cannot combine either with surfactants (reducing their efficacy) or with Carbonate and Sulfate ions (giving lime incrustation). Sequestering agents (also called chelants or complexing agents) are useful in preventing various metals (iron, copper, etc.) oxides stains too.

In machine dishwashing, their presence is of primary importance.

In machine laundry, they give a number of benefits: lower lime incrustations on fabrics, better rinsability of the same detergent from textures, so that a lower quantity of chemicals remains on clothes to be weared.

Usually, sequestering agents present in both conventional and ecologic detergents are NOT ecologic:

    EDTA and sodium salt (C.A.S. 60-00-4 e 64-02-8):
    they're very little biodegradable. Recently it was measured a slow biodegradation at alkaline pH and in absence of heavy metals; however these conditions are usually available neither in nature nor in wastewater treatment plants. (European Union - Risk Assessment Report Vol.49: “Edetic acid (EDTA)”, 2004).

  • PHOSPHONATES (ATMP - C.A.S. 6419-19-8; EDTMP – C.A.S. 1429-50-1; HDTMP – C.A.S. 23605-74-5; DTPMP – C.A.S. 15827-60-8; HEDP, etidronic acid – C.A.S. 2809-21-4):
    they're very little aerobically biodegradable (HERA – Human & Environmental Risk Assessment on ingredients of European household cleaning products: “Phosphonates”, 2004) and almost not at all anaerobically (Danish EPA: “Environmental and Health Assessment of Substances in Household and Cosmetic Detergent products”, 96-100, 615-2001); in certain conditions, (catalysis by transiction metals ions, at specific pH ranges) they're photodegradable; however, in natural environment photodegradation is prevented by other physico-chemical conditions, such as the lower and lower solar light exposure going deeper and deeper in surface water, or the very high absorption by soils and sediments, which is reversible only by action of strong acids or very salted solutions (FISCHER K: “Distribution and elimination of HEDP in aquatic test systems”, WATER RES; 27 (3). 1993. 485-493).

  • POLICARBOXYLATED (acrilyc acid omopolymers – C.A.S. 9003-04-7 and 9003-01-4; acrilyc acid and maleic anhydride copolymers – C.A.S. 52255-49-9):
    they're very little aerobically and not at all anaerobically biodegradable; in wastewater treatment plants, they are adsorbed by sludges (Danish EPA: “Environmental and Health Assessment of Substances in Household and Cosmetic Detergent products”, 100-103, 615-2001).

  • NTA (nitrilotriacetic acid - CAS: 139-13-9):
    in Italy it is used for some industrial applications, while in Europe (particularly in Germany and Switzerland) it is a common ecologic detergents component. Its features are conflicting, because it is very biodegradable, but biodegradation reaction byproducts are carcinogen nitrosamines.

Bensos uses only very low environmental and toxicologic impact sequestering agents:

    N,N-diacetic glutamic acid tetrasodium salt (GLDA – C.A.S. 51981-21-6) - natural source;

  • iminodisuccinic acid tetrasodium salt (IDS – C.A.S. 144538-83-0);

  • sodium gluconate (C.A.S. 527-07-1) - natural source;

  • sodium citrate (C.A.S. 6132-04-3) - natural source.

They're all readily biodegradable (OECD Tests 301 A-F) and show a very low toxicity against both aquatic organisms and human health.

We patented in Italy some of these molecules application in detergents and we're requiring to extend this patent internationally (PCT).

PRESERVATIVES

These chemicals are able to prevent degradation of products by microorganisms, so that products storing time can be longer.

Usually, preservatives contained in both conventional and ecologic detergents are slowly biodegradable, highly toxic for aquatic organisms and allergizing. For example:

    5-chloro-2-methyl-2H-isothiazolyn-3-one (C.A.S. 26172-55-4), mutagen according to the Ames Test;

  • 2-methyl-2H-isothiazolyn-3-one (C.A.S. 2682-20-4), mutagen according to the Ames Test;

  • 2-bromo-2-nitropropan-1,3-diol (Bronopol, C.A.S. 52-51-7), which gives carcinogen nitrosamines as biodegradation byproducts;

  • sodium hydroxymethylglycinate (C.A.S. 70161-44-3), Formaldehyde donor. IARC consideres Formaldehyde “probably human carcinogen” - Carc 2A);

  • DMDM Hydantoin (C.A.S. 7732-18-5), Formaldehyde donor.

A preservative contained in an environmentally friendly detergent should be active against bacteria and/or fungi only to the end of storing time (from some months to maximum 2 years, depending on the category of product). When it has come into wastewater and it has been diluted, it must be degradable by bacteria living in the environment and in treatment plants.

2-phenoxyethanol (C.A.S. 122-99-6), commonly used in cosmetics, is readily biodegradable and shows good acute toxicologic properties; however, it may contain impurities of phenol (C.A.S. 108-95-2), toxic chemical (IARC upd. 1999: Carc. 3 - not classifiable as to its carcinogenity to humans, nor doubtless to animals) which shows many mutation and reproductive defects data, even if generally at high doses. Indeed, our 2-phenoxyethanol producer assures that this product contains max 10 mg/Kg phenol (0,001 % by wt). Bensos' trials show that the sole sodium lactate is inadequate as preservative on neutral pH formulations, so we think that it is better to add a little bit of 2-phenoxyethanol; therefore the full product contains only maximum 0,00001 % of phenol. This seems to be reasonable, also because phenol DOESN'T show a tendency to bioaccumulate (Log Kow = 1,45 < 3). It is important to be sure that the detergent, if it is well-stocked, is free from pathogenic microorganisms.

Benzoic acid and its salts (C.A.S. 532-32-1) have good toxicologic and ecotoxicologic properties, but show some technical limitations in use.

There is a preservative category, very commonly used in cosmetics and sometimes in food, that recently has been investigated: PARABENS. There are very interesting public documents, available at the following link: Opinions of European Commission Scientific Committee - Health Going to read the chapter “Preservatives”, you may open the following links: Parabens COLIPA no. P82, Parabens, underarm cosmetics and breast cancer (where they point out that parabens and breast cancer are NOT related) and The safety evaluation of Parabens covering in addition isopropyl paraben. These documents are the overall evaluation of many scientific researches (chosen as the most reliable from the technical point of view); they show that actually some chemicals among the Parabens are concerning because of their bad toxicologic profiles: propylparaben, isopropyl paraben and butylparaben.
Anyway, they also show that other molecules are safe: methylparaben and ethylparaben have both good toxicologic properties, so that CE considers them safe for food too.

Among Bensos' products, the ones needing preservatives contain the following chemicals:

    lactic acid (C.A.S. 79-33-4) or its salt (C.A.S. 867-56-1), natural source food additives that show moisturizing properties too.

  • 2-phenoxyethanol (C.A.S. 122-99-6) as bactericide in some formulations (0,5-1,0% by weight);

  • sodium chloride (common salt for cooking, C.A.S. 7647-14-5), which in certain condition may cause bacteria cellular membranes break, due to its hygroscopicity. In detergents, usually it must be coupled with other antibacterial agents for technical reasons.

  • methylparaben sodium salt (C.A.S. 5026-62-0) as antifungal in some formulations (0,2% by weight);



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