The ingredients of the covid-19 vaccine are considered safe and polysorbate-80 is been used for years

A thread enumerating eight alleged ingredients that vaccines may contain (without specifying any brand) is circulating these days in WhatsApp. This is a FALSE list, as it is not true that vaccines are composed of all (or most) of them and there is no evidence that the injection or the ingredient itself causes these side effects in the supplied proportions.

"Can you tell me the components of the vaccine that you want to receive? As they are likely to say no, here you have is a list of some of them: aluminium (causes Alzheimer), thimerosal (autism), polysorbate-80 (sterility, lowered immunity and inflammation), sorbitol trioleate (inflammations), neomycin and deoxycholate (are immunotoxins), gentamicin (encephalitis), formaldehyde and 'netapropylectone' (carcinogenic), polymyxin and squalene (neurotoxic)"

Of all the cited ingredients, only polysorbate-80, an emulsifier, beta-propiolactone (incorrectly written in the message) and aluminium (but as a hydroxide) are present in some of the vaccines against covid-19 which have package inserts available. Containing polysorbate-80 are the vials of AstraZeneca, Janssen, CanSino, Covishield and Sputnik V, as can be observed in the prospect pamphlets of each drug. The beta-propiolactone are used in a Chinese vaccine, Sinopharm Wuhan, to inactivate the viral vector. The aluminium salts, which work as adjuvant since the 1970’s, have been seen in vaccines CoronaVac, Covaxin and Epivac; the aluminium also works as a compound of the envelopes of vaccines.


Polysorbate-80 is only associated with some inflammation. Although the message ensures that it causes “sterility, lowered immunity and inflammation”, there is no scientific evidence supporting this. It is a molecule that is used in some injections against flu and other diseases —in fact, many childhood vaccines such as Prevenar, Gardasil 9 or Trumenba contain polysorbate—. It also acts as an adjuvant, that is, it is “a product enforcing its action” helping to increase the immunologic response of the patient, explains Rafael Padrós, responsible of the Occupational Risk Prevention Service at the “Hospital de la Santa Creu i Sant Pau” and expert in vaccines. Moreover, this compound is also used as stabiliser and emulsifier in the food industry. Beta-propiolactone, on its side, is carcinogenic in a natural manner in other circumstances, but not in the way it has been used in the vaccine.

Drug regulatory agencies such as the European or the American insist that both polysorbate-80 and the rest of the ingredients used to make vaccines are safe in the quantities they contain. In fact, for any medicine to be approved, different clinical trials must be done showing that they are effective and, above all, safe, as the Spanish Association of Vaccinology explains. This does not mean they are not going to cause side effects —all drugs in the world do have them— but at least it has been guaranteed that “the most severe reactions are very infrequent”.

The other elements

Among the compounds cited in the message, some elements are indeed used as ingredients to make vaccines, but not in covid-19 vaccines. Thimerosal is used in some flu vaccines, although its presence in the manufacture and preservation of some vaccines is decreasing; sorbitol trioleate is an ingredient of some flu vaccines and is considered as an agent able to cause some allergic reaction; neomycin is a compound in some vaccines for flu or rabies, for example, or gentamicin, polymyxin or squalene, all of which are used in vaccines usually distributed in Spain but not in those combating coronavirus, according to the list of vaccines and allergens of the Spanish Paediatrics Association. Desoxycholate is a drug that is injected into the neck area to reduce fat.

MRC-5 is not pulmonary tissue from an aborted foetus

The message also cites among the alleged ingredients of the vaccine the MRC-5, which it claims is defined as pulmonary tissue from an aborted foetus. This is MISLEADING, as we have already explained, because although some vaccines have been made from embryonic cells, they are laboratory-derived copies and in none of these cases is it MRC-5.

"Can you tell me the components of the vaccine that you want to receive? As they are likely to say no, here you have a list of some of them [...] MRC-5 is pulmonary tissue from an aborted 14-week Caucasian male foetus, look this up on wikipedia as well"

Cell lines are cells of a single type (mainly animal cells) that have been modified to reproduce endlessly in the laboratory and which are mainly used in research. In their origin, according to an article in Nature, cell lines used in the AstraZeneca manufacturing, whose name is HEK-293, were obtained from human embryonic kidney cells in the 1970’s. Jahnssen’s vaccine has also used cell lines, in this case PER.C6, derived from embryonic retinal cells developed in 1985, according to a Nature paper. The MRC-5 are another type of cell lines, in such a case yes, obtained from a lung tissue coming from a 14-week male foetus legally aborted in 1966 but they have not been used for any of the covid-19 vaccines. 

This does not mean that a vaccine is made from cells coming from aborted human babies, but that researchers originally needed these cells coming from a very specific foetus to obtain a cell line like embryonic kidney cells.

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