Included in our scope of accreditation under the Campden Laboratory Accreditation Scheme.
Preservative efficacy (challenge) testing provides a means of predicting preservative adequacy under normal conditions of storage and use and constitutes a key element of product safety assessment and shelf life/PAO substantiation.
Unless otherwise instructed, it is our policy to apply the BP/EP method with the addition of E coli for topical products. In our view, this offers maximum regulatory acceptability combined with the most reliable prediction of preservative efficacy. However, whether you use the pharmacopoeial tests, EN ISO 11930, your own in house protocol or a combination of various methods, we are committed to providing the best possible service, tailored to suit your individual requirements. We are happy to include supplementary test organisms, on either a single or mixed culture basis, and to retest after a period of accelerated storage to confirm microbial stability over shelf life and PAO in the case of personal care products. Reliably predictive data in the case of aggressive or preservative tolerant strains can be particularly difficult to generate and is an area in which DLL has considerable experience.
Where requested, performed in accordance with EP 2.6.12.
In addition to providing signed master copies of final reports, it is our standard practice to provide interim updates by email after each inspection point. This enables clients to track sample performance and provides early warning of possible shortcomings. Where development schedules are tight an early indication can be essential to achieving deadlines and launch dates.
Preservative challenge testing can be discontinued at any stage, if so requested. Under these circumstances, DLL will only charge for work completed up to the point of termination.
|Test||Turnaround (days)||Min sample requirement||Price/sample|
|BP/EP (5 organism)/USP||40 (max)||150g/ml||£175|
|BP/EP (4 organism – topicals)||40 (max)||100g/ml||£140|
|Additional inocula (single or mixed culture)||40 (max)||As above + 30g/ml per inoculum||As above + £45 per extra inoculum|
|EN ISO 11930||40 (max)||150g/ml||£175|
|In house (mixed culture)||40 (max)||75g/ml||£110|
|Client specific methods||Designated storage period plus 10 days||30g/ml per inoculum||PoA|
|Dilution-neutralisation validation (EP 2.6.13)||3 (bacteria)|
|20g/ml||£60 (in combination with challenge) £75 (if conducted alone)|
|Wipe in pack||40 (max)||6 packs||£220.00|
All prices exclude VAT