Assistant Microbiologist Jobs in Missouri (NOW HIRING)

Lief Labs is a premier formulation, product development, and manufacturing partner for leading dietary supplement brands. Our world‑class R&D and Product Development teams create innovative, great‑tasting formulations, while our state‑of‑the‑art cGMP manufacturing facility delivers scalable, turnkey solutions that help entrepreneurial companies build and grow successful brands.

We are seeking a QC Microbiologist to join our Quality Control team in Valencia, California. This is an exciting opportunity for a microbiology professional who thrives in a GMP‑regulated environment and is passionate about product safety, quality, compliance, and continuous improvement.

In this role, you will serve as a key microbiological resource supporting the testing and release of raw materials, packaging components, in‑process materials, and finished products while helping maintain the highest standards of quality and regulatory compliance.

• Perform microbiological testing of raw materials, packaging components, in‑process samples, finished products, and environmental monitoring samples.
• Conduct testing for APC, Yeast & Mold, Coliforms, E. coli, Salmonella, Staphylococcus aureus, and other applicable microorganisms.
• Review and interpret laboratory results to ensure compliance with FDA, USP, and internal specifications.
• Maintain accurate, complete, and auditable laboratory documentation in accordance with GMP, GLP, and data integrity requirements.
• Execute environmental monitoring programs, including air, surface, water, and personnel monitoring.
• Support cleaning validation, sanitization verification, equipment qualification, and contamination control initiatives.
• Conduct ATP and microbiological swabbing activities and evaluate results.
• Assist in assessing microbiological risks related to new equipment, facility modifications, and process changes.

• Lead or support investigations involving out‑of‑specification (OOS), atypical, or nonconforming laboratory results.
• Perform root cause analysis and support corrective and preventive actions (CAPA).
• Participate in customer complaint investigations involving microbiological concerns.
• Author and revise SOPs, validation protocols, test methods, technical reports, and controlled quality documents.

• Partner with Quality Assurance, Production, Sanitation, R&D, and Operations teams to support product quality and safety initiatives.
• Provide microbiological expertise during audits, inspections, and quality investigations.
• Assist with microbiology, sanitation, and GMP training for laboratory and production personnel.
• Support internal audits, supplier audits, and client or regulatory inspections.

• Bachelor's degree in Microbiology or a related scientific discipline.

• Minimum 5 years of experience in a GMP‑regulated microbiology laboratory.
• Experience within dietary supplements, pharmaceuticals, food manufacturing, or a related regulated industry preferred.
• Hands‑on experience performing microbiological testing and environmental monitoring activities.
• Experience supporting audits and inspections in a regulated environment.

• Strong understanding of USP microbiological methods including USP 61, 62, 2021, and 2022.
• Knowledge of FDA regulations, including 21 CFR Part 111 and 21 CFR Part 117.
• Experience with method validation, investigations, CAPA, and technical report writing.
• Familiarity with LIMS and electronic laboratory systems are preferred.
• Working knowledge of cGMP, GLP, GDP, and laboratory safety requirements.
• Strong analytical, troubleshooting, and problem‑solving abilities.
• Excellent documentation and technical writing skills.
• Exceptional attention to detail and organizational skills.
• Ability to communicate scientific information effectively to cross‑functional teams.
• Self‑motivated, adaptable, and able to manage multiple priorities in a fast‑paced manufacturing environment.
• Proficiency with Microsoft Office applications.

• Regular standing, walking, bending, kneeling, crouching, reaching, and lifting throughout the workday.
• Frequently lift and move items up to 10 pounds and occasionally up to 20 pounds.
• Ability to perform laboratory work requires close attention to detail and visual accuracy.
• Laboratory and manufacturing environment supporting dietary supplement production.
• Exposure to raw materials, including common allergens such as milk, eggs, fish, shellfish, tree nuts, peanuts, wheat, and soy.
• Clean, organized, and safety‑focused workplace.

Salary Range: $74,000 - $88,000 annually

Starting pay for the successful applicant depends on a variety of job‑related factors, including but not limited to market demands, experience, training, skills, and education.

• Medical, Dental, and Vision Insurance
• 401(k) with Company Participation
• Life Insurance
• Education Reimbursement Program
• Paid Time Off (PTO)

At Lief Labs, you'll have the opportunity to make a direct impact on product quality and consumer safety while working alongside industry experts in a growing and innovative organization. If you're passionate about microbiology, quality excellence, and continuous improvement, we invite you to apply.

Lief is an Equal Opportunity/Affirmative Action employer. All qualified applicants will receive consideration for employment without regard to race, color, religion, sex including sexual orientation and gender identity, national origin, disability, protected Veteran Status, or any other characteristic protected by applicable federal, state, or local law.

If you are a qualified individual with a disability or a disabled veteran, you have the right to request an accommodation if you are unable or limited in your ability to use or access our career center as a result of your disability. To request accommodation, contact the Lief Human Resources department.

Lief will consider employment-qualified applicants with criminal histories in a manner consistent with the requirements of the Los Angeles Fair Chance Initiative for Hiring.

Lief uses E-Verify to confirm work eligibility in the United States. E-Verify compares the information on your Form I-9, Employment Eligibility Verification, to official government records.