Straight record, it is highly likely you and your husband have been exposed to Organophosphates from the engine oil. To confirm if it is at a level in your blood stream you could get tested at a clinic in London upon your return called Biolab Medical Unit, an environmental medicine clinic. (I have no financial interest in this establishment by the way).
If you continue to have symptoms, respiratory or neurologically you could potentially claim for Aerotoxic damages against the airline, but it’s a long process.
Here are some links to educate yourselves on this issue which aircrew have been campaigning to prevent events like this happening. Airlines can fit filters but are in denial that it’s an issue worth spending the £10k per aircraft on. Profits before health it seems. DHL cargo airlines have fitted them on their aircraft so at least the mail and parcels are safe.
https://www.aerotoxic.org/