Sans Quiros, a sales executive for Dow Packaging and Specialty Plastics in Latin America, does not mean that people should not advocate for themselves in the workplace.

Rather, she believes that sometimes the value of silence is not fully appreciated. She says "listen before you speak" is the best career advice she's received.

"Through my career in sales, I have learned that silence is the best way to get the information you need," she said. "Silence is power. It helps you to empathize and think about the right answer.

"If you are smart enough to handle silence moments, you will have the power to manage any difficult situation," she said.

The 35-year-old is based in Mexico City, where she's the sales director for Dow's packaging and specialty plastics business in the north region of Latin America.

She was initially drawn to plastics because of the size of the industry. She had a degree in chemical engineering from the Universidad Iberoamericana in Mexico City.

"As a chemical engineer, you want to belong to one of the largest petrochemical industries, and Dow was and continues to be the largest one," she said.

But over time she's come to a deeper appreciation.

"Later on, as I kept growing with the company and with the market, I understood that this industry is fascinating because you have the power to replace any type of product with plastic having the right chemistry, while helping the environment," Sans Quiros said.

"I like to educate people about how plastics has made our lives easier," she said, in areas like reducing food waste, improving transportation, helping to deliver potable water "to unimaginable places" and making human health better.

But she also said she wants to work to see that the plastics industry improves its environmental profile.

Asked to identify a coveted future job, she said she wants "to be part of a project to reduce plastic waste, increasing plastics use."

"I think this industry is one of the best to innovate about how to do things differently," she said. "You have enough space to try new business models, new products at different markets [and] enable customers to target new applications."

One area she said she's paying attention to is nanotechnology: "Besides the uncertainty about the potential risks of nanomaterials, this technology will define the future of plastics."

It's a constantly changing industry, she said, and requires a near continuous focus on personal change to work in.

"This industry has taught me how not to take a 'no' for an answer," she said. "You can be as creative as you want and you will succeed. Current molds only help you to define the first stage of your dream. The next one, depends on you."