The acute cytotoxicities of four cosmetic ingredients: a preservative, imidazolidinylurea (IU) and three mild surfactants, cocamido propyl hydroxy sultaine (CAS), magnesium laureth sulfate (Mg LES), and decyl glucoside (APG) were studied using sea urchin eggs. The cellular targets of these compounds were identified by studying the effects on calcium homeostasis, intracellular pH, sodium and potassium contents, protein and DNA synthesis, and protein phosphorylation. These compounds inhibited the first cleavage of sea urchin eggs in a dose-dependent fashion with half maximal doses (IC50) from 30 microg/ml for Mg LES, 60 microg/ml for IU, 83 microg/ml for CAS, to above 400 microg/ml for APG. The time at which a compound showed the greatest toxicity to the cell cycle was definable for APG (between 20 and 50 min postfertilization) and IU (from fertilization to 50 min later); the other compounds being toxic throughout division. Compounds exhibited toxicity to a wide range of cellular targets. IU, the least toxic, mainly operates through inhibition of protein and DNA syntheses. CAS and Mg LES produced nonspecific cytotoxicity related to alterations of membrane and endomembrane permeabilities resulting in ionic disequilibrium (Na+, K+, Ca2+) and inhibition of intracellular storage of Ca2+. The APG effect mainly involved intracellular pH and DNA synthesis, a hypothesis suggested by the narrow postfertilization period of maximal toxicity (1).

References__________________________________________

(1) Mechanisms of cytotoxicity by cosmetic ingredients in sea urchin eggs.
Amouroux I, Pesando D, Noël H, Girard JP.
Arch Environ Contam Toxicol. 1999 Jan;36(1):28-37.

Magnesium Laureth Sulfate  is a chemical compound obtained by ethoxylation from Ethylene oxide, a chemical compound that is rather controversial due to its composition in which traces of impurities hazardous to human health may be found. Surfactant widely used in cosmetics as a cleaning agent.

Used in shampoos and liquid soaps, this component lessens the skin when compared to other surfactant products. It is therefore suitable for the most sensitive and delicate skins.

In people with particularly sensitive skin it could cause allergy.

For more information:

Magnesium Laureth Sulfate studies

Molecular Formula: C₃₆H₇₄MgO₁₄S₂

Molecular Weight: 819.399 g/mol

CAS: 62755-21-9

EC Number: 613-078-1

Synonyms:

• Magnesium Laureth-5 Sulfate
• Magnesium Laureth-8 Sulfate
• Magnesium Laureth-16 Sulfate
• Poly(oxy-1,2-ethanediyl), .alpha.-sulfo-.omega.-(dodecyloxy)-, magnesium salt