chapter  35
16 Pages

Quality Control of Finished Sunscreen Products

Introduction 719

Product Forms 721

Sampling 721

Physical Methods 722

Chemical Methods 725

Spectroscopy 726

Chromatography 727

Validation 728

Microbiology 729

Efficacy 730

Stability 730

Summary 730

References 731


Any description of the techniques for product quality control should start with an

agreed definition of the term. The description almost requires that the question

“Why do quality control at all?” be asked. In the modern times of Good

Manufacturing Practices (GMP) (1,2), speed to market, just-in-time processes,

and government mandated development and production, quality control of the

finished product is almost an expensive complication delaying the release of

finished products. The reality is that even with the best systems in place, with

all of the supplier qualifications completed, with a regular auditing process,

and with government oversight, there is still a need to ensure that material

produced will meet the expectations of the final consumer. One could probably

find many definitions of quality and a number of systems to ensure product

quality. For the purposes of this chapter, quality is defined as meeting the custo-

mer’s expectations every time. Such an approach is described, for example, by

Juran and Godfrey (3), who indicate two aspects of quality. The first definition

covers the features of products that meet customer needs and thereby provide

customer satisfaction. The second is the freedom from deficiencies, which

could result in the need for rework or lead to product failure and therefore

customer dissatisfaction. This latter aspect has, for the most part, been addressed

through conformance to specifications. This grew from a belief that if something

meets specifications, it will satisfy the customer. Newer approaches with greater

emphasis on customer focus require that a broader view be taken, that quality is

not always captured only in specifications. From such a view grows the definition

of quality control as a universal managerial process for conducting operations so

as to provide stability-to prevent adverse change and to maintain the status quo.

The quality control process maintains this stability by evaluating actual perform-

ance, comparing actual performance to goals and acting on differences found (3).

This chapter does not pretend to cover all of the aspects one must understand,

address and control to have a quality system or even a quality control system.

It also does not cover quality assurance (defined as verification that control is

being maintained), quality improvement, “total quality management,” or other

extensions of these concepts and philosophies. This is an ever-evolving area

and today’s definitions are likely to change again in the future. Many volumes

have been written on that. Quality control is a program with the steps taken by

the developer and manufacturer to support delivery to the customer’s expec-

tation. Quality control focuses on control during operations and meeting the

goals for operations. Quality assurance is involved at later steps and interacts

with a broader range of functions involved in the product life cycle.