This article reviews various occupational and environmental exposures that may be of concern during lactation.

For more detailed information and references on specific medications and substances, please refer to LactMed, e-lactancia, Infant Risk, or Mother to Baby. Further information on ingredients in cosmetics can be found at the Cosmetic Ingredient Review.

Massage is a wonderful therapy for maternal self-care during lactation to assist with stress relief. While there are some special considerations during lactation as noted below, there is no absolute indication to pump and dump after massage.

Gentle massage techniques are preferred, especially around the breasts and chest. Aggressive techniques around the breasts and chest can disturb the milk-producing tissue, leading to breast inflammation, swelling, pain, and the possibility of reduced milk production.¹

Vibration is known to improve blood flow² and can be an enjoyable part of massage.  However, avoid electronic vibrators around the breasts and chest, as they can cause disturbance to the milk-producing tissue.

Essential oils may be used in massage oil, or in aromatherapy. Essential oils are generally recognized as safe (“GRAS”) by the FDA. However, they should be used judiciously as there is limited research on the safety of essential oils in humans.

In general, the ICEA (International Childbirth Education Association)³ and NAHA (National Association of Holistic Aromatherapy) advised against applying undiluted essential oils directly to the skin.  Do not directly ingest essential oils since the concentrations are much higher than concentrations found in whole food.

There is limited research showing risks and benefits for some commonly used essential oils in the breastfeeding population:

• Coconut Oil: One study found that topical application of coconut oil reduced formation of nipple cracks and nipple pain in the early postpartum period.⁴
• Tea Tree Oil: One study found that topical application of tea tree oil reduced formation of nipple cracks and nipple pain in the early postpartum period.⁴ There are case reports of young children with prepubertal gynecomastia⁵ or premature thelarche⁶ in association with direct exposure to lavender or tea tree oils. There is no evidence that maternal exposure alone increases these risks to the child.
• Lavender: Aromatherapy with citrus or lavender improved sexual satisfaction in breastfeeding women, however this study did not include any lactation-specific outcomes in its results.⁷ There are case reports of young children with prepubertal gynecomastia⁵ or premature thelarche⁶ in association with direct exposure to lavender or tea tree oils. There is no evidence that maternal exposure alone increases these risks to the child.
• Citrus: Aromatherapy with citrus or lavender improved sexual satisfaction in breastfeeding women, however this study did not include any lactation-specific outcomes in its results.⁷
• Peppermint: Peppermint⁸ has been shown to decrease milk production. For more information about herbs to suppress lactation, see the section on Agents that Decrease Milk Production.
• Sage: Sage⁸ has been shown to decrease milk production. For more information about herbs to suppress lactation, see the section on Agents that Decrease Milk Production.

Cosmetic Ingredient Review (CIR) assesses the safety of many chemicals in hair dyes, but there is not a comprehensive review of dye ingredients, and risks have not been documented.

There are two major types of hair dye:

• Oxidative: used for permanent or semipermanent treatments.  More frequently associated with adverse health outcomes.
• Non-oxidative: used for temporary or semipermanent treatments.⁹

There is no specific evidence for increased health risk to individuals who use hair dye during lactation. However, general risks to the consumer and/or beauty worker from hair dye products include the following:⁹

• Bladder cancer risk is increased in beauty workers who have been exposed for 10+ years. This is related to exposure to arylamines.
• Breast cancer risk is inconclusive among consumers.
• Lymphoma risk is increased in consumers by ~ 20% and increases an additional ~25% when using hair dye monthly or more frequently.

There is evidence for childhood cancers related to maternal hair dying during pregnancy or lactation:

• Acute myelogenous leukemia risk is increased in children whose mothers used hair dye during breastfeeding.¹⁰
• Malignant germ cell tumors are increased for sons and daughters when mothers use hair dye during breastfeeding.¹¹
• Neuroblastoma risk is increased in children whose mothers used hair dye during pregnancy and one month before conception.¹² No evidence exists for exposure during breastfeeding.

There is no absolute indication to pump and dump after use of hair dyes. As it pertains to the possible increased risk of childhood cancers, consider infrequent use of hair dye during lactation, and if able to achieve the desired cosmetic effect, consider using non-oxidative dyes rather than oxidative dyes.

Tattoos are increasingly common. Some studies have looked at the composition of inks, which include organic colorants and a wide range of metal salts. The composition can vary widely, and an Italian study published in the Lancet¹³ found some metals exceeded the safe allergological limit (Cr, Ni, Co) or exceeded safe toxic levels (Cd, Mn, pb, Sb, V, and rarely, Hg).  There are no reported cases of health problems in children after a birthing or lactating parent receives a tattoo during lactation or pregnancy.  However, we do not know the biokinetics and systemic effect of the chemical compounds of tattoo inks. Additionally, we do not have reliable data on the transport of elements used in tattoo ink into breastmilk or transfer to the fetus via the placenta.¹⁴ While there is no absolute indication to pump and dump it is reasonable for most individuals to postpone this elective procedure until after weaning due to the lack of consistency in ink composition and the lack of safety data on ink components.

Botox is used in aesthetics for treatment and/or prevention of wrinkles, and also used for medical problems such as migraines, dystonia, hyperhidrosis, limb spasticity, blepharospasm and strabismus.

There are several brands of botulinum type A or type B, and the molecular structure varies based on which brand is used. Large molecular weight molecules typically do not enter the milk compartment. Botox, Dysport and Myobloc are larger molecules (300-900kDa). Xeomin is 150kDa, similar to Humira, which has been shows to enter the milk compartment in low levels.¹⁵

Evidence for safety of Botox treatment during lactation is starting to emerge.  A 2024 study by Hudson et al tested breastmilk samples in a 5-day period following injections of 40-92 U of botulinum toxin and found no botulinum toxin in half of the breastmilk samples and low levels of botulinum toxin in the other half of the samples. All samples were well below the lethal oral dose for an infant.¹⁶

There is no absolute indication to pump and dump. Out of an abundance of caution, using a preparation with a larger molecular structure for cosmetic treatments during lactation may be preferred.

There are many agents used in facial cosmetics with limited data on their safety during lactation.

In general, the Cosmetic Ingredient Review(CIR) Expert Panel advised there is low toxicity from parabens at concentrations used in cosmetics.¹⁷

A French systematic review¹⁸ found that use of cosmetics by women in the perinatal period was associated with higher urine levels of phenols, parabens, plasticizers (e.g., phthalates), and phenoxyethanol in the women.   Direct cosmetic use in children was associated with higher urinary concentration of phthalates. This review did not look at the concentrations of these chemicals in breastfed infants of lactating parents using these cosmetics.

A small study demonstrated that endocrine disrupting chemicals (EDCs) in a face lotion during pregnancy were associated with an increased risk of infant testicular germ cell tumors (TGCT).¹⁹ Other products (e.g., perfume, hairspray, nail polish, hair dye, permanent wave, body lotion, deodorant, sunscreen) were not associated with TGCT risk in this study.  We know that EDCs cross the placenta²⁰ and have been found in breastmilk.²¹ Although studies have not been done on the effects of using these products on breastfed infants, the above data suggests a theoretical concern for health risks to children due to EDCs used during lactation.

There are no absolute indications to pump and dump. Out of caution, consider minimizing number of products and frequency of application, and choosing products that have short ingredient lists, don’t contain perfume, and can easily be rinsed off.¹⁸

Firefighters have unique occupational hazards due to their exposures. Currently there is no known evidence of harm to the child when breastfeeding and working as a firefighter.^22,23

• Cancer: Volatile compounds released during combustion, including PFAS (perfluoroalkyl and polyfluoroalkyl substances) and PAH (polycyclic aromatic hydrocarbons), are known to increase cancer among populations of firefighters. Additional exposure to emergency vehicle and equipment diesel exhaust and flame retardants exposes firefighters to chlorinated tris, polybrominated diphenyl ether, and more PFAS.²⁴ Often these chemicals are small enough to pass easily through most modern firefighter gear, and then absorbed via inhalation, ingestion, or directly through the skin.²⁵ Limited data suggests minimal changes in the presence and effects of some of these compounds in human milk after exposure to fire compared to baseline populations.^22,23

Firefighters should follow standard decontamination procedures after responding to a fire. While data is limited, there is no absolute indication to pump and dump.

By following standard safety guidelines and tracking exposure, it is possible to work in radiology departments with minimal risk to the breastfed child. There is no absolute indication to pump and dump.

For more information on imaging during lactation, see the articles on “Radiology” on the TPD Index Page.