The issue often comes up as to whether or not aluminium, a recognised toxin, is used as an adjuvant, meaning an ingredient which helps create a stronger immune response. It is no surprise that claim that vaccines contain aluminium is hotly denied. To meet that, here is a peer-reviewed article with a reference, and an abstract. It is explicitly stated that aluminium is a demonstrated neurotoxin and the most commonly used vaccine adjuvant. How can that be good? It is not.

https://pubmed.ncbi.nlm.nih.gov/21568886/

Curr Med Chem

.2011;18(17):2630-7.

 doi: 10.2174/092986711795933740.

Aluminum vaccine adjuvants: are they safe?

L Tomljenovic , C A Shaw

Affiliations expand

• DOI: 10.2174/092986711795933740

Abstract

Aluminium is an experimentally demonstrated neurotoxin and the most commonly used vaccine adjuvant. Despite almost 90 years of widespread use of aluminium adjuvants, medical science's understanding about their mechanisms of action is still remarkably poor. There is also a concerning scarcity of data on toxicology and pharmacokinetics of these compounds. In spite of this, the notion that aluminium in vaccines is safe appears to be widely accepted. Experimental research, however, clearly shows that aluminium adjuvants have a potential to induce serious immunological disorders in humans. In particular, aluminium in adjuvant form carries a risk for autoimmunity, long-term brain inflammation and associated neurological complications and may thus have profound and widespread adverse health consequences. In our opinion, the possibility that vaccine benefits may have been overrated and the risk of potential adverse effects underestimated, has not been rigorously evaluated in the medical and scientific community. We hope that the present paper will provide a framework for a much needed and long overdue assessment of this highly contentious medical issue.”

 As far as I am aware, that comprehensive assessment has not been undertaken.  

https://www.statnews.com/2022/09/27/possible-link-aluminum-childhood-vaccines-asthma-risk-caveats/

https://bmjopen.bmj.com/content/12/6/e058795

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4615573/#:~:text=Aluminium%20adjuvant%2Dcontaining%20vaccines%20can,reproducing%20these%20symptoms%20%5B34%5D.