TRISYL^® Silica

Activated bleaching earths (ABE or clay) and diatomaceous earth (DE) contain crystalline silica and detectable levels of metal oxides. TRISYL^® silicas are chemically inert and do not promote adverse oil oxidation reactions.

The above data shows the chemical makeup of TRISYL^® silica, clay/ABE and DE. The data reveals detectable levels of crystalline silica in clay and DE. Data was compiled and averaged using multiple sources analyzing the composition of multiple clays available today.¹

On a dry basis, TRISYL^® silica adsorbents are highly pure (>99.9%) amorphous silicon dioxide (SiO2).

Amorphous silica is considered safe for food processing applications by the U.S. Food and Drug Administration (FDA) and the European Food and Safety Authority (EFSA) ² U.S. and EU authorities have no occupational exposure limits applicable to amorphous silica. Some EU Member States have established OELs, but these values are not harmonized.³ Grace applies the German TRGS 900 limit of 4 mg/m3 respirable. 

As declared by Industrial Minerals Europe (IMA-Europe) via their website safesilica.edu, “regarding product classification, in accordance with the CLP Regulation, industrial minerals producers have jointly determined it appropriate to classify crystalline silica (fine fraction) (quartz (fine fraction) and cristobalite (fine fraction)) as STOT RE1 for the silicosis hazard. The fine fraction of crystalline silica is the relevant fraction, which can potentially reach the deep lung, as defined by EN 481.”⁴ Per the above, STOT refers to Specific Target Organ Toxicity, and RE refers to Repeated Exposure. Learn more here.

A study published in Archives of Toxicology and made available by the National Library of Medicine reveals that respirable crystalline silica dust particles are small enough to penetrate deep into the lungs and cause irreversible pulmonary damage. A few respiratory illnesses and diseases known to be associated with crystalline silica dust include silicosis, bronchitis, lung cancer, and tuberculosis. ⁵ Naturally sourced amorphous silica adsorbents, such as bleaching clays and diatomaceous earth, can often be contaminated with crystalline silica and thus require extra safety precautions during operational exposure. 

Grace engineered TRISYL^® silica to be chemically inert with a large surface area and a controlled, consistent composition. TRISYL^® silica prevents oxidative side reactions during the adsorption process so spent filter cake does not have the potential to auto-ignite during disposal. 

Also due to its hydrogel nature, TRISYL^® silica adsorbents have a lower dust potential compared to dry adsorbents with a moisture content less than 10%. Choosing Grace’s synthetic, amorphous TRISYL^® silica technology allows edible oil and biofuel producers to maximize their refinery’s productivity and sustainability without having to compromise on their employees' occupational safety.

1. https://patentimages.storage.googleapis.com/ac/f1/1d/9e4d0fc5e2089d/US5008226.pdf and https://www.chembk.com/en/chem/Sud%20Chemie%20Tonsil%20Optimum%20FF 
2. Fruijtier-Pölloth, C. The safety of nanostructured synthetic amorphous silica (SAS) as a food additive (E 551). Arch Toxicol 90, 2885–2916 (2016). https://doi.org/10.1007/s00204-016-1850-4
3. 29 CFR 1910.1053; OSHA FAQ on Crystalline silica standard, https://www.osha.gov/silica-crystalline/background-info (see FAQ "What is crystalline silica?"); https://eur-lex.europa.eu/legal-content/EN/TXT/HTML/?uri=CELEX:52016PC0248&from=FR; and Directive (EU) 2017/2398 amending Directive 2004/37/EC on the protection of workers from the risks related to exposure to carcinogens or mutagens at work.*National workplace exposure inventories should be consulted.
4. Industrial Minerals Europe (IMA-Europe). Crystalline silica: The science. Safesilica.eu https://safesilica.eu/crystalline-silica-the-science/ 
5. Merget R, Bauer T, Küpper HU, Philippou S, Bauer HD, Breitstadt R, Bruening T. Health hazards due to the inhalation of amorphous silica. Arch Toxicol. 2002 Jan;75(11-12):625-34. doi: 10.1007/s002040100266. PMID: 11876495.