If you are worried about sending mail for security reasons, you can send an encrypted email message using a PGP Key
“eM Client PGP Documentation”
https://www.emclient.com/webdocumentation/en/10.0/emclient/default.htm#E-mail/PGP.htm
Quote:- from the above link.
“PGP is a public key encryption program that has become the most popular standard for email encryption - it follows the OpenPGP standard (RFC 4880) for encrypting and decrypting data”.
“Each user has an encryption key that is publicly known and a private key that is known only to that user. To send encrypted messages you need the public key of your recipient. To decrypt a message sent to you, you will use your private key to decrypt it”.
Also see the below eM Client webpages on How to setup PGP encryption.
“Email Encryption and Digital Signature”
Quick guide to email encryption and email digital signatures in eM Client
https://www.emclient.com/email-encryption
eM Client also has its on Public encryption key directory you can u/l & manage your public keys.
“What is eM Keybook”
https://support.emclient.com/index.php?/Knowledgebase/Article/View/221/6/what-is-em-keybook
Quote extract below from the above link:-
“eM Keybook is a public encryption key directory managed by the company eM Client.
It’s an online service where you can upload and manage your public keys so anyone can easily send you encrypted messages and you can easily get public keys of the recipients you want to send encrypted messages to”.